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class="toctree-l3"><a class="reference internal" href="../tutorial/perform-findAndModify-linearizable-reads.html">Linearizable Reads via <code class="docutils literal"><span class="pre">findAndModify</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../core/query-plans.html">Query Plans</a></li><li class="toctree-l3"><a class="reference internal" href="../core/query-optimization.html">Query Optimization</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/evaluate-operation-performance.html">Evaluate Performance of Current Operations</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/optimize-query-performance-with-indexes-and-projections.html">Optimize Query Performance</a></li><li class="toctree-l4"><a class="reference internal" href="../core/write-performance.html">Write Operation Performance</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/explain-results.html">Explain Results</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/analyze-query-plan.html">Analyze Query Performance</a></li><li class="toctree-l3"><a class="reference internal" href="../core/tailable-cursors.html">Tailable Cursors</a></li></ul></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../aggregation.html">Aggregation</a><ul><li class="toctree-l2"><a class="reference internal" href="../core/aggregation-pipeline.html">Aggregation Pipeline</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/aggregation-pipeline-optimization.html">Aggregation Pipeline Optimization</a></li><li class="toctree-l3"><a class="reference internal" href="../core/aggregation-pipeline-limits.html">Aggregation Pipeline Limits</a></li><li class="toctree-l3"><a class="reference internal" href="../core/aggregation-pipeline-sharded-collections.html">Aggregation Pipeline and Sharded Collections</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/aggregation-zip-code-data-set.html">Example with ZIP Code Data</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/aggregation-with-user-preference-data.html">Example with User Preference Data</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/map-reduce.html">Map-Reduce</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/map-reduce-sharded-collections.html">Map-Reduce and Sharded Collections</a></li><li class="toctree-l3"><a class="reference internal" href="../core/map-reduce-concurrency.html">Map-Reduce Concurrency</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/map-reduce-examples.html">Map-Reduce Examples</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/perform-incremental-map-reduce.html">Perform Incremental Map-Reduce</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/troubleshoot-map-function.html">Troubleshoot the Map Function</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/troubleshoot-reduce-function.html">Troubleshoot the Reduce Function</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/aggregation.html">Aggregation Reference</a><ul><li class="toctree-l3"><a class="reference internal" href="../meta/aggregation-quick-reference.html">Aggregation Pipeline Quick Reference</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/operator/aggregation/interface.html">Aggregation Commands</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/aggregation-commands-comparison.html">Aggregation Commands Comparison</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/aggregation-variables.html">Variables in Aggregation Expressions</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/sql-aggregation-comparison.html">SQL to Aggregation Mapping Chart</a></li></ul></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../data-modeling.html">Data Models</a><ul><li class="toctree-l2"><a class="reference internal" href="../core/data-modeling-introduction.html">Data Modeling Introduction</a></li><li class="toctree-l2"><a class="reference internal" href="../core/schema-validation.html">Schema Validation</a></li><li class="toctree-l2"><a class="reference internal" href="../core/data-models.html">Data Modeling Concepts</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/data-model-design.html">Data Model Design</a></li><li class="toctree-l3"><a class="reference internal" href="../core/data-model-operations.html">Operational Factors and Data Models</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../applications/data-models.html">Data Model Examples and Patterns</a><ul><li class="toctree-l3"><a class="reference internal" href="../applications/data-models-relationships.html">Model Relationships Between Documents</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-embedded-one-to-one-relationships-between-documents.html">Model One-to-One Relationships with Embedded Documents</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-embedded-one-to-many-relationships-between-documents.html">Model One-to-Many Relationships with Embedded Documents</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-referenced-one-to-many-relationships-between-documents.html">Model One-to-Many Relationships with Document References</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../applications/data-models-tree-structures.html">Model Tree Structures</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-tree-structures-with-parent-references.html">Model Tree Structures with Parent References</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-tree-structures-with-child-references.html">Model Tree Structures with Child References</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-tree-structures-with-ancestors-array.html">Model Tree Structures with an Array of Ancestors</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-tree-structures-with-materialized-paths.html">Model Tree Structures with Materialized Paths</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-tree-structures-with-nested-sets.html">Model Tree Structures with Nested Sets</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../applications/data-models-applications.html">Model Specific Application Contexts</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-data-for-atomic-operations.html">Model Data for Atomic Operations</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-data-for-keyword-search.html">Model Data to Support Keyword Search</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-data-for-schema-versioning.html">Model Data for Schema Versioning</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-monetary-data.html">Model Monetary Data</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-time-data.html">Model Time Data</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/model-computed-data.html">Model Computed Data</a></li></ul></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/data-models.html">Data Model Reference</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/database-references.html">Database References</a></li></ul></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../core/transactions.html">Transactions</a><ul><li class="toctree-l2"><a class="reference internal" href="../core/transactions-in-applications.html">Drivers API</a></li><li class="toctree-l2"><a class="reference internal" href="../core/transactions-production-consideration.html">Production Considerations</a></li><li class="toctree-l2"><a class="reference internal" href="../core/transactions-sharded-clusters.html">Production Considerations (Sharded Clusters)</a></li><li class="toctree-l2"><a class="reference internal" href="../core/transactions-operations.html">Transactions and Operations</a></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../indexes.html">Indexes</a><ul><li class="toctree-l2"><a class="reference internal" href="../core/index-single.html">Single Field Indexes</a></li><li class="toctree-l2"><a class="reference internal" href="../core/index-compound.html">Compound Indexes</a></li><li class="toctree-l2"><a class="reference internal" href="../core/index-multikey.html">Multikey Indexes</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/multikey-index-bounds.html">Multikey Index Bounds</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/index-text.html">Text Indexes</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/specify-language-for-text-index.html">Specify a Language for Text Index</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/avoid-text-index-name-limit.html">Specify Name for <code class="docutils literal"><span class="pre">text</span></code> Index</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/control-results-of-text-search.html">Control Search Results with Weights</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/limit-number-of-items-scanned-for-text-search.html">Limit the Number of Entries Scanned</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/index-wildcard.html">Wildcard Indexes</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/index-wildcard-restrictions.html">Wildcard Index Restrictions</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/2dsphere.html"><code class="docutils literal"><span class="pre">2dsphere</span></code> Indexes</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/query-a-2dsphere-index.html">Query a <code class="docutils literal"><span class="pre">2dsphere</span></code> Index</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/2d.html"><code class="docutils literal"><span class="pre">2d</span></code> Indexes</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/build-a-2d-index.html">Create a <code class="docutils literal"><span class="pre">2d</span></code> Index</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/query-a-2d-index.html">Query a <code class="docutils literal"><span class="pre">2d</span></code> Index</a></li><li class="toctree-l3"><a class="reference internal" href="../core/geospatial-indexes.html"><code class="docutils literal"><span class="pre">2d</span></code> Index Internals</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/calculate-distances-using-spherical-geometry-with-2d-geospatial-indexes.html">Calculate Distance Using Spherical Geometry</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/geohaystack.html"><code class="docutils literal"><span class="pre">geoHaystack</span></code> Indexes</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/build-a-geohaystack-index.html">Create a Haystack Index</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/query-a-geohaystack-index.html">Query a Haystack Index</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/index-hashed.html">Hashed Indexes</a></li><li class="toctree-l2"><a class="reference internal" href="../core/index-properties.html">Index Properties</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/index-ttl.html">TTL Indexes</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/expire-data.html">Expire Data from Collections by Setting TTL</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../core/index-unique.html">Unique Indexes</a></li><li class="toctree-l3"><a class="reference internal" href="../core/index-partial.html">Partial Indexes</a></li><li class="toctree-l3"><a class="reference internal" href="../core/index-case-insensitive.html">Case Insensitive Indexes</a></li><li class="toctree-l3"><a class="reference internal" href="../core/index-sparse.html">Sparse Indexes</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/index-creation.html">Index Builds on Populated Collections</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/build-indexes-on-replica-sets.html">Build Indexes on Replica Sets</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/build-indexes-on-sharded-clusters.html">Build Indexes on Sharded Clusters</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/index-intersection.html">Index Intersection</a></li><li class="toctree-l2"><a class="reference internal" href="../tutorial/manage-indexes.html">Manage Indexes</a></li><li class="toctree-l2"><a class="reference internal" href="../tutorial/measure-index-use.html">Measure Index Use</a></li><li class="toctree-l2"><a class="reference internal" href="../applications/indexes.html">Indexing Strategies</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/create-indexes-to-support-queries.html">Create Indexes to Support Your Queries</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/sort-results-with-indexes.html">Use Indexes to Sort Query Results</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/ensure-indexes-fit-ram.html">Ensure Indexes Fit in RAM</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/create-queries-that-ensure-selectivity.html">Create Queries that Ensure Selectivity</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/indexes.html">Indexing Reference</a></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../security.html">Security</a><ul><li class="toctree-l2"><a class="reference internal" href="../administration/security-checklist.html">Security Checklist</a></li><li class="toctree-l2"><a class="reference internal" href="../tutorial/enable-authentication.html">Enable Access Control</a></li><li class="toctree-l2"><a class="reference internal" href="../core/authentication.html">Authentication</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/security-users.html">Users</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/create-users.html">Add Users</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../core/authentication-mechanisms.html">Authentication Mechanisms</a><ul><li class="toctree-l4"><a class="reference internal" href="../core/security-scram.html">SCRAM</a></li><li class="toctree-l4"><a class="reference internal" href="../core/security-x.509.html">x.509</a><ul><li class="toctree-l5"><a class="reference internal" href="../tutorial/configure-x509-client-authentication.html">Use x.509 Certificates to Authenticate Clients</a></li></ul></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../core/authentication-mechanisms-enterprise.html">Enterprise Authentication Mechanisms</a><ul><li class="toctree-l4"><a class="reference internal" href="../core/kerberos.html">Kerberos Authentication</a><ul><li class="toctree-l5"><a class="reference internal" href="../tutorial/control-access-to-mongodb-with-kerberos-authentication.html">Configure MongoDB with Kerberos Authentication on Linux</a></li><li class="toctree-l5"><a class="reference internal" href="../tutorial/control-access-to-mongodb-windows-with-kerberos-authentication.html">Configure MongoDB with Kerberos Authentication on Windows</a></li><li class="toctree-l5"><a class="reference internal" href="../tutorial/troubleshoot-kerberos.html">Troubleshoot Kerberos Authentication</a></li><li class="toctree-l5"><a class="reference internal" href="../tutorial/kerberos-auth-activedirectory-authz.html">Configure MongoDB with Kerberos Authentication and Active Directory Authorization</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../core/security-ldap.html">LDAP Proxy Authentication</a><ul><li class="toctree-l5"><a class="reference internal" href="../tutorial/configure-ldap-sasl-activedirectory.html">Authenticate Using SASL and LDAP with ActiveDirectory</a></li><li class="toctree-l5"><a class="reference internal" href="../tutorial/configure-ldap-sasl-openldap.html">Authenticate Using SASL and LDAP with OpenLDAP</a></li><li class="toctree-l5"><a class="reference internal" href="../tutorial/authenticate-nativeldap-activedirectory.html">Authenticate and Authorize Users Using Active Directory via Native LDAP</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../core/security-ldap-external.html">LDAP Authorization</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../core/security-internal-authentication.html">Internal/Membership Authentication</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/deploy-replica-set-with-keyfile-access-control.html">Deploy Replica Set With Keyfile Authentication</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/enforce-keyfile-access-control-in-existing-replica-set.html">Update Replica Set to Keyfile Authentication</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/enforce-keyfile-access-control-in-existing-replica-set-without-downtime.html">Update Replica Set to Keyfile Authentication (No Downtime)</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/rotate-key-replica-set.html">Rotate Keys for Replica Sets</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/deploy-sharded-cluster-with-keyfile-access-control.html">Deploy Sharded Cluster with Keyfile Authentication</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/enforce-keyfile-access-control-in-existing-sharded-cluster.html">Update Sharded Cluster to Keyfile Authentication</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/enforce-keyfile-access-control-in-existing-sharded-cluster-no-downtime.html">Update Sharded Cluster to Keyfile Authentication (No Downtime)</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/rotate-key-sharded-cluster.html">Rotate Keys for Sharded Clusters</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/configure-x509-member-authentication.html">Use x.509 Certificate for Membership Authentication</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/upgrade-keyfile-to-x509.html">Upgrade from Keyfile Authentication to x.509 Authentication</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/rotate-x509-membership-certificates.html">Rolling Update of x.509 Cluster Certificates that Contain New DN</a></li></ul></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/authorization.html">Role-Based Access Control</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/built-in-roles.html">Built-In Roles</a></li><li class="toctree-l3"><a class="reference internal" href="../core/security-user-defined-roles.html">User-Defined Roles</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/manage-users-and-roles.html">Manage Users and Roles</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/change-own-password-and-custom-data.html">Change Your Password and Custom Data</a></li><li class="toctree-l3"><a class="reference internal" href="../core/collection-level-access-control.html">Collection-Level Access Control</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/security-transport-encryption.html">TLS/SSL (Transport Encryption)</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-ssl.html">Configure <code class="docutils literal"><span class="pre">mongod</span></code> and <code class="docutils literal"><span class="pre">mongos</span></code> for TLS/SSL</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-ssl-clients.html">TLS/SSL Configuration for Clients</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/upgrade-cluster-to-ssl.html">Upgrade a Cluster to Use TLS/SSL</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-fips.html">Configure MongoDB for FIPS</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/security-encryption-at-rest.html">Encryption at Rest</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-encryption.html">Configure Encryption</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/rotate-encryption-key.html">Rotate Encryption Keys</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/security-client-side-encryption.html">Client-Side Field Level Encryption</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/security-automatic-client-side-encryption.html">Automatic Client-Side Field Level Encryption</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/security-client-side-automatic-json-schema.html">Automatic Encryption Rules</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/security-client-side-query-aggregation-support.html">Read/Write Support with Automatic Field Level Encryption</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/security-client-side-encryption-appendix.html">Appendix</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../core/security-explicit-client-side-encryption.html">Explicit (Manual) Client-Side Field Level Encryption</a></li><li class="toctree-l3"><a class="reference internal" href="../core/security-client-side-encryption-key-management.html">Master Key and Data Encryption Key Management</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/manage-client-side-encryption-data-keys.html">Manage Data Encryption Keys</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/security-client-side-encryption-limitations.html">Limitations</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/auditing.html">Auditing</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-auditing.html">Configure Auditing</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-audit-filters.html">Configure Audit Filters</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/audit-message.html">System Event Audit Messages</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/security-hardening.html">Network and Configuration Hardening</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/security-mongodb-configuration.html">IP Binding</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-linux-iptables-firewall.html">Configure Linux <code class="docutils literal"><span class="pre">iptables</span></code> Firewall for MongoDB</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-windows-netsh-firewall.html">Configure Windows <code class="docutils literal"><span class="pre">netsh</span></code> Firewall for MongoDB</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../tutorial/implement-field-level-redaction.html">Implement Field Level Redaction</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/security.html">Security Reference</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/system-roles-collection.html"><code class="docutils literal"><span class="pre">system.roles</span></code> Collection</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/system-users-collection.html"><code class="docutils literal"><span class="pre">system.users</span></code> Collection</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/resource-document.html">Resource Document</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/privilege-actions.html">Privilege Actions</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../tutorial/create-a-vulnerability-report.html">Create a Vulnerability Report</a></li><li class="toctree-l2"><a class="reference internal" href="../appendix/security.html">Appendix</a><ul><li class="toctree-l3"><a class="reference internal" href="../appendix/security/appendixA-openssl-ca.html">Appendix A - OpenSSL CA Certificate for Testing</a></li><li class="toctree-l3"><a class="reference internal" href="../appendix/security/appendixB-openssl-server.html">Appendix B - OpenSSL Server Certificates for Testing</a></li><li class="toctree-l3"><a class="reference internal" href="../appendix/security/appendixC-openssl-client.html">Appendix C - OpenSSL Client Certificates for Testing</a></li></ul></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../changeStreams.html">Change Streams</a><ul><li class="toctree-l2"><a class="reference internal" href="../administration/change-streams-production-recommendations.html">Change Streams Production Recommendations</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/change-events.html">Change Events</a></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../replication.html">Replication</a><ul><li class="toctree-l2"><a class="reference internal" href="../core/replica-set-members.html">Replica Set Members</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/replica-set-primary.html">Replica Set Primary</a></li><li class="toctree-l3"><a class="reference internal" href="../core/replica-set-secondary.html">Replica Set Secondary Members</a><ul><li class="toctree-l4"><a class="reference internal" href="../core/replica-set-priority-0-member.html">Priority 0 Replica Set Members</a></li><li class="toctree-l4"><a class="reference internal" href="../core/replica-set-hidden-member.html">Hidden Replica Set Members</a></li><li class="toctree-l4"><a class="reference internal" href="../core/replica-set-delayed-member.html">Delayed Replica Set Members</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../core/replica-set-arbiter.html">Replica Set Arbiter</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/replica-set-oplog.html">Replica Set Oplog</a></li><li class="toctree-l2"><a class="reference internal" href="../core/replica-set-sync.html">Replica Set Data Synchronization</a></li><li class="toctree-l2"><a class="reference internal" href="../core/replica-set-architectures.html">Replica Set Deployment Architectures</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/replica-set-architecture-three-members.html">Three Member Replica Sets</a></li><li class="toctree-l3"><a class="reference internal" href="../core/replica-set-architecture-geographically-distributed.html">Replica Sets Distributed Across Two or More Data Centers</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/replica-set-high-availability.html">Replica Set High Availability</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/replica-set-elections.html">Replica Set Elections</a></li><li class="toctree-l3"><a class="reference internal" href="../core/replica-set-rollbacks.html">Rollbacks During Replica Set Failover</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../applications/replication.html">Replica Set Read and Write Semantics</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/replica-set-write-concern.html">Write Concern for Replica Sets</a></li><li class="toctree-l3"><a class="reference internal" href="../core/read-preference.html">Read Preference</a><ul><li class="toctree-l4"><a class="reference internal" href="../core/read-preference-tags.html">Tag Sets</a></li><li class="toctree-l4"><a class="reference internal" href="../core/read-preference-staleness.html">maxStalenessSeconds</a></li><li class="toctree-l4"><a class="reference internal" href="../core/read-preference-use-cases.html">Read Preference Use Cases</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../core/read-preference-mechanics.html">Server Selection Algorithm</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../administration/replica-set-deployment.html">Replica Set Deployment Tutorials</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/deploy-replica-set.html">Deploy a Replica Set</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/deploy-replica-set-for-testing.html">Deploy a Replica Set for Testing and Development</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/deploy-geographically-distributed-replica-set.html">Deploy a Geographically Redundant Replica Set</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/add-replica-set-arbiter.html">Add an Arbiter to Replica Set</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/convert-standalone-to-replica-set.html">Convert a Standalone to a Replica Set</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/expand-replica-set.html">Add Members to a Replica Set</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/remove-replica-set-member.html">Remove Members from Replica Set</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/replace-replica-set-member.html">Replace a Replica Set Member</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../administration/replica-set-member-configuration.html">Member Configuration Tutorials</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/adjust-replica-set-member-priority.html">Adjust Priority for Replica Set Member</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-secondary-only-replica-set-member.html">Prevent Secondary from Becoming Primary</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-a-hidden-replica-set-member.html">Configure a Hidden Replica Set Member</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-a-delayed-replica-set-member.html">Configure a Delayed Replica Set Member</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-a-non-voting-replica-set-member.html">Configure Non-Voting Replica Set Member</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/convert-secondary-into-arbiter.html">Convert a Secondary to an Arbiter</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../administration/replica-set-maintenance.html">Replica Set Maintenance Tutorials</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/change-oplog-size.html">Change the Size of the Oplog</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/perform-maintence-on-replica-set-members.html">Perform Maintenance on Replica Set Members</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/force-member-to-be-primary.html">Force a Member to Become Primary</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/resync-replica-set-member.html">Resync a Member of a Replica Set</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-replica-set-tag-sets.html">Configure Replica Set Tag Sets</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/reconfigure-replica-set-with-unavailable-members.html">Reconfigure a Replica Set with Unavailable Members</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/manage-chained-replication.html">Manage Chained Replication</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/change-hostnames-in-a-replica-set.html">Change Hostnames in a Replica Set</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/configure-replica-set-secondary-sync-target.html">Configure a Secondary’s Sync Target</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/replication.html">Replication Reference</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/replica-configuration.html">Replica Set Configuration</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/replica-set-protocol-versions.html">Replica Set Protocol Version</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/troubleshoot-replica-sets.html">Troubleshoot Replica Sets</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/local-database.html">The <code class="docutils literal"><span class="pre">local</span></code> Database</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/replica-states.html">Replica Set Member States</a></li></ul></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../sharding.html">Sharding</a><ul><li class="toctree-l2"><a class="reference internal" href="../core/sharded-cluster-components.html">Sharded Cluster Components</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/sharded-cluster-shards.html">Shards</a></li><li class="toctree-l3"><a class="reference internal" href="../core/sharded-cluster-config-servers.html">Config Servers (metadata)</a></li><li class="toctree-l3"><a class="reference internal" href="../core/sharded-cluster-query-router.html">Router (mongos)</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/sharding-shard-key.html">Shard Keys</a></li><li class="toctree-l2"><a class="reference internal" href="../core/hashed-sharding.html">Hashed Sharding</a></li><li class="toctree-l2"><a class="reference internal" href="../core/ranged-sharding.html">Ranged Sharding</a></li><li class="toctree-l2"><a class="reference internal" href="../tutorial/deploy-shard-cluster.html">Deploy a Sharded Cluster</a></li><li class="toctree-l2"><a class="reference internal" href="../core/zone-sharding.html">Zones</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/manage-shard-zone.html">Manage Shard Zones</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/sharding-segmenting-data-by-location.html">Segmenting Data by Location</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/sharding-tiered-hardware-for-varying-slas.html">Tiered Hardware for Varying SLA or SLO</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/sharding-segmenting-shards.html">Segmenting Data by Application or Customer</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/sharding-high-availability-writes.html">Distributed Local Writes for Insert Only Workloads</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/sharding-data-partitioning.html">Data Partitioning with Chunks</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/create-chunks-in-sharded-cluster.html">Create Chunks in a Sharded Cluster</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/split-chunks-in-sharded-cluster.html">Split Chunks in a Sharded Cluster</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/merge-chunks-in-sharded-cluster.html">Merge Chunks in a Sharded Cluster</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/modify-chunk-size-in-sharded-cluster.html">Modify Chunk Size in a Sharded Cluster</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/sharding-balancer-administration.html">Balancer</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/manage-sharded-cluster-balancer.html">Manage Sharded Cluster Balancer</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/migrate-chunks-in-sharded-cluster.html">Migrate Chunks in a Sharded Cluster</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../administration/sharded-cluster-administration.html">Administration</a><ul><li class="toctree-l3"><a class="reference internal" href="../administration/sharded-cluster-config-servers.html">Config Server Administration</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/replace-config-server.html">Replace a Config Server</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/view-sharded-cluster-configuration.html">View Cluster Configuration</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/restart-sharded-cluster.html">Restart a Sharded Cluster</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/migrate-sharded-cluster-to-new-hardware.html">Migrate a Sharded Cluster to Different Hardware</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/add-shards-to-shard-cluster.html">Add Shards to a Cluster</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/remove-shards-from-cluster.html">Remove Shards from an Existing Sharded Cluster</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/clear-jumbo-flag.html">Clear <code class="docutils literal"><span class="pre">jumbo</span></code> Flag</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/backup-sharded-cluster-metadata.html">Back Up Cluster Metadata</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/convert-sharded-cluster-to-replica-set.html">Convert Sharded Cluster to Replica Set</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/convert-replica-set-to-replicated-shard-cluster.html">Convert a Replica Set to a Sharded Cluster</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/convert-shard-standalone-to-shard-replica-set.html">Convert a Shard Standalone to a Shard Replica Set</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/sharding.html">Sharding Reference</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/sharded-cluster-requirements.html">Operational Restrictions</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/troubleshoot-sharded-clusters.html">Troubleshoot Sharded Clusters</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/config-database.html">Config Database</a></li></ul></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../administration.html">Administration</a><ul><li class="toctree-l2"><a class="reference internal" href="../administration/production-notes.html">Production Notes</a></li><li class="toctree-l2"><a class="reference internal" href="../administration/production-checklist-operations.html">Operations Checklist</a></li><li class="toctree-l2"><a class="reference internal" href="../administration/production-checklist-development.html">Development Checklist</a></li><li class="toctree-l2"><a class="reference internal" href="../administration/analyzing-mongodb-performance.html">Performance</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/manage-the-database-profiler.html">Database Profiler</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/database-profiler.html">Database Profiler Output</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/transparent-huge-pages.html">Disable Transparent Huge Pages (THP)</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/ulimit.html">UNIX <code class="docutils literal"><span class="pre">ulimit</span></code> Settings</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../administration/configuration-and-maintenance.html">Configuration and Maintenance</a><ul><li class="toctree-l3"><a class="reference internal" href="../administration/configuration.html">Run-time Database Configuration</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/upgrade-revision.html">Upgrade to the Latest Revision of MongoDB</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/manage-mongodb-processes.html">Manage <code class="docutils literal"><span class="pre">mongod</span></code> Processes</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/terminate-running-operations.html">Terminate Running Operations</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/rotate-log-files.html">Rotate Log Files</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../data-center-awareness.html">Data Center Awareness</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/workload-isolation.html">Workload Isolation in MongoDB Deployments</a></li><li class="toctree-l3"><a class="reference internal" href="../core/zone-sharding.html">Zones</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/manage-shard-zone.html">Manage Shard Zones</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/sharding-segmenting-data-by-location.html">Segmenting Data by Location</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/sharding-tiered-hardware-for-varying-slas.html">Tiered Hardware for Varying SLA or SLO</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/sharding-segmenting-shards.html">Segmenting Data by Application or Customer</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/sharding-high-availability-writes.html">Distributed Local Writes for Insert Only Workloads</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/manage-shard-zone.html">Manage Shard Zones</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/backups.html">MongoDB Backup Methods</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/backup-with-filesystem-snapshots.html">Back Up and Restore with Filesystem Snapshots</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/backup-and-restore-tools.html">Back Up and Restore with MongoDB Tools</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/restore-replica-set-from-backup.html">Restore a Replica Set from MongoDB Backups</a></li><li class="toctree-l3"><a class="reference internal" href="../administration/backup-sharded-clusters.html">Backup and Restore Sharded Clusters</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/backup-sharded-cluster-with-filesystem-snapshots.html">Back Up a Sharded Cluster with File System Snapshots</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/backup-sharded-cluster-with-database-dumps.html">Back Up a Sharded Cluster with Database Dumps</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/schedule-backup-window-for-sharded-clusters.html">Schedule Backup Window for Sharded Clusters</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/restore-sharded-cluster.html">Restore a Sharded Cluster</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/recover-data-following-unexpected-shutdown.html">Recover a Standalone after an Unexpected Shutdown</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../administration/monitoring.html">Monitoring for MongoDB</a><ul><li class="toctree-l3"><a class="reference internal" href="../administration/free-monitoring.html">Free Monitoring</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/monitor-with-snmp.html">Monitor MongoDB With SNMP on Linux</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/monitor-with-snmp-on-windows.html">Monitor MongoDB Windows with SNMP</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/troubleshoot-snmp.html">Troubleshoot SNMP</a></li></ul></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../storage.html">Storage</a><ul><li class="toctree-l2"><a class="reference internal" href="../core/storage-engines.html">Storage Engines</a><ul><li class="toctree-l3"><a class="reference internal" href="../core/wiredtiger.html">WiredTiger Storage Engine</a><ul><li class="toctree-l4"><a class="reference internal" href="../tutorial/change-standalone-wiredtiger.html">Change Standalone to WiredTiger</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/change-replica-set-wiredtiger.html">Change Replica Set to WiredTiger</a></li><li class="toctree-l4"><a class="reference internal" href="../tutorial/change-sharded-cluster-wiredtiger.html">Change Sharded Cluster to WiredTiger</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../core/inmemory.html">In-Memory Storage Engine</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/journaling.html">Journaling</a><ul><li class="toctree-l3"><a class="reference internal" href="../tutorial/manage-journaling.html">Manage Journaling</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../core/gridfs.html">GridFS</a></li><li class="toctree-l2"><a class="reference internal" href="../faq/storage.html">FAQ: MongoDB Storage</a></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../faq.html">Frequently Asked Questions</a><ul><li class="toctree-l2"><a class="reference internal" href="../faq/fundamentals.html">FAQ: MongoDB Fundamentals</a></li><li class="toctree-l2"><a class="reference internal" href="../faq/indexes.html">FAQ: Indexes</a></li><li class="toctree-l2"><a class="reference internal" href="../faq/concurrency.html">FAQ: Concurrency</a></li><li class="toctree-l2"><a class="reference internal" href="../faq/sharding.html">FAQ: Sharding with MongoDB</a></li><li class="toctree-l2"><a class="reference internal" href="../faq/replica-sets.html">FAQ: Replication and Replica Sets</a></li><li class="toctree-l2"><a class="reference internal" href="../faq/storage.html">FAQ: MongoDB Storage</a></li><li class="toctree-l2"><a class="reference internal" href="../faq/diagnostics.html">FAQ: MongoDB Diagnostics</a></li></ul></li><li class="toctree-l1"><a class="reference internal" href="../reference.html">Reference</a><ul><li class="toctree-l2"><a class="reference internal" href="../reference/operator.html">Operators</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/operator/query.html">Query and Projection Operators</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/operator/query-comparison.html">Comparison Query Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/eq.html">$eq</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/gt.html">$gt</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/gte.html">$gte</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/in.html">$in</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/lt.html">$lt</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/lte.html">$lte</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/ne.html">$ne</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/nin.html">$nin</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/query-logical.html">Logical Query Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/and.html">$and</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/not.html">$not</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/nor.html">$nor</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/or.html">$or</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/query-element.html">Element Query Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/exists.html">$exists</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/type.html">$type</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/query-evaluation.html">Evaluation Query Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/expr.html">$expr</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/jsonSchema.html">$jsonSchema</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/mod.html">$mod</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/regex.html">$regex</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/text.html">$text</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/where.html">$where</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/query-geospatial.html">Geospatial Query Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/geoIntersects.html">$geoIntersects</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/geoWithin.html">$geoWithin</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/near.html">$near</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/nearSphere.html">$nearSphere</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/box.html">$box</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/center.html">$center</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/centerSphere.html">$centerSphere</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/geometry.html">$geometry</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/maxDistance.html">$maxDistance</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/minDistance.html">$minDistance</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/polygon.html">$polygon</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/uniqueDocs.html">$uniqueDocs</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/query-array.html">Array Query Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/all.html">$all</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/elemMatch.html">$elemMatch (query)</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/size.html">$size</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/query-bitwise.html">Bitwise Query Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/bitsAllClear.html">$bitsAllClear</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/bitsAllSet.html">$bitsAllSet</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/bitsAnyClear.html">$bitsAnyClear</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/query/bitsAnySet.html">$bitsAnySet</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/query/comment.html">$comment</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/projection.html">Projection Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/projection/positional.html">$ (projection)</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/projection/elemMatch.html">$elemMatch (projection)</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/projection/meta.html">$meta</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/projection/slice.html">$slice (projection)</a></li></ul></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/operator/update.html">Update Operators</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/operator/update-field.html">Field Update Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/currentDate.html">$currentDate</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/inc.html">$inc</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/min.html">$min</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/max.html">$max</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/mul.html">$mul</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/rename.html">$rename</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/set.html">$set</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/setOnInsert.html">$setOnInsert</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/unset.html">$unset</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/update-array.html">Array Update Operators</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/positional.html">$ (update)</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/positional-all.html">$[]</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/positional-filtered.html">$[&lt;identifier&gt;]</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/addToSet.html">$addToSet</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/pop.html">$pop</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/pull.html">$pull</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/push.html">$push</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/pullAll.html">$pullAll</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/each.html">$each</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/position.html">$position</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/slice.html">$slice</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/sort.html">$sort</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/update-bitwise.html">Bitwise Update Operator</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/operator/update/bit.html">$bit</a></li></ul></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/operator/aggregation-pipeline.html">Aggregation Pipeline Stages</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/addFields.html">$addFields (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/bucket.html">$bucket (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/bucketAuto.html">$bucketAuto (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/collStats.html">$collStats (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/count.html">$count (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/currentOp.html">$currentOp (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/facet.html">$facet (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/geoNear.html">$geoNear (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/graphLookup.html">$graphLookup (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/group.html">$group (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/indexStats.html">$indexStats (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/limit.html">$limit (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/listLocalSessions.html">$listLocalSessions</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/listSessions.html">$listSessions</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/lookup.html">$lookup (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/match.html">$match (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/merge.html">$merge (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/out.html">$out (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/planCacheStats.html">$planCacheStats</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/project.html">$project (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/redact.html">$redact (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/replaceRoot.html">$replaceRoot (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/replaceWith.html">$replaceWith (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/sample.html">$sample (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/set.html">$set (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/skip.html">$skip (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/sort.html">$sort (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/sortByCount.html">$sortByCount (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/unset.html">$unset (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/unwind.html">$unwind (aggregation)</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/operator/aggregation.html">Aggregation Pipeline Operators</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/abs.html">$abs (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/acos.html">$acos (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/acosh.html">$acosh (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/add.html">$add (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/addToSet.html">$addToSet (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/allElementsTrue.html">$allElementsTrue (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/and.html">$and (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/anyElementTrue.html">$anyElementTrue (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/arrayElemAt.html">$arrayElemAt (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/arrayToObject.html">$arrayToObject (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/asin.html">$asin (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/asinh.html">$asinh (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/atan.html">$atan (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/atan2.html">$atan2 (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/atanh.html">$atanh (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/avg.html">$avg (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/ceil.html">$ceil (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/cmp.html">$cmp (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/concat.html">$concat (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/concatArrays.html">$concatArrays (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/cond.html">$cond (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/convert.html">$convert (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/cos.html">$cos (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/dateFromParts.html">$dateFromParts (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/dateToParts.html">$dateToParts (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/dateFromString.html">$dateFromString (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/dateToString.html">$dateToString (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/dayOfMonth.html">$dayOfMonth (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/dayOfWeek.html">$dayOfWeek (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/dayOfYear.html">$dayOfYear (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/degreesToRadians.html">$degreesToRadians (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/divide.html">$divide (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/eq.html">$eq (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/exp.html">$exp (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/filter.html">$filter (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/first.html">$first (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/floor.html">$floor (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/gt.html">$gt (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/gte.html">$gte (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/hour.html">$hour (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/ifNull.html">$ifNull (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/in.html">$in (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/indexOfArray.html">$indexOfArray (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/indexOfBytes.html">$indexOfBytes (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/indexOfCP.html">$indexOfCP (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/isArray.html">$isArray (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/isoDayOfWeek.html">$isoDayOfWeek (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/isoWeek.html">$isoWeek (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/isoWeekYear.html">$isoWeekYear (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/last.html">$last (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/let.html">$let (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/literal.html">$literal (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/ln.html">$ln (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/log.html">$log (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/log10.html">$log10 (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/lt.html">$lt (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/lte.html">$lte (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/ltrim.html">$ltrim (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/map.html">$map (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/max.html">$max (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/mergeObjects.html">$mergeObjects (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/meta.html">$meta (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/min.html">$min (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/millisecond.html">$millisecond (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/minute.html">$minute (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/mod.html">$mod (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/month.html">$month (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/multiply.html">$multiply (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/ne.html">$ne (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/not.html">$not (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/objectToArray.html">$objectToArray (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/or.html">$or (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/pow.html">$pow (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/push.html">$push (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/radiansToDegrees.html">$radiansToDegrees (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/range.html">$range (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/reduce.html">$reduce (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/regexFind.html">$regexFind (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/regexFindAll.html">$regexFindAll (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/regexMatch.html">$regexMatch (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/reverseArray.html">$reverseArray (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/round.html">$round (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/rtrim.html">$rtrim (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/second.html">$second (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/setDifference.html">$setDifference (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/setEquals.html">$setEquals (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/setIntersection.html">$setIntersection (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/setIsSubset.html">$setIsSubset (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/setUnion.html">$setUnion (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/size.html">$size (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/sin.html">$sin (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/slice.html">$slice (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/split.html">$split (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/sqrt.html">$sqrt (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/stdDevPop.html">$stdDevPop (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/stdDevSamp.html">$stdDevSamp (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/strcasecmp.html">$strcasecmp (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/strLenBytes.html">$strLenBytes (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/strLenCP.html">$strLenCP (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/substr.html">$substr (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/substrBytes.html">$substrBytes (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/substrCP.html">$substrCP (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/subtract.html">$subtract (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/sum.html">$sum (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/switch.html">$switch (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/tan.html">$tan (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toBool.html">$toBool (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toDate.html">$toDate (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toDecimal.html">$toDecimal (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toDouble.html">$toDouble(aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toInt.html">$toInt (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toLong.html">$toLong (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toObjectId.html">$toObjectId (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toString.html">$toString (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toLower.html">$toLower (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/toUpper.html">$toUpper (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/trim.html">$trim (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/trunc.html">$trunc (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/type.html">$type (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/week.html">$week (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/year.html">$year (aggregation)</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/aggregation/zip.html">$zip (aggregation)</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/operator/query-modifier.html">Query Modifiers</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/comment.html">$comment</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/explain.html">$explain</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/hint.html">$hint</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/max.html">$max</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/maxTimeMS.html">$maxTimeMS</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/min.html">$min</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/orderby.html">$orderby</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/query.html">$query</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/returnKey.html">$returnKey</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/showDiskLoc.html">$showDiskLoc</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/operator/meta/natural.html">$natural</a></li></ul></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/command.html">Database Commands</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-aggregation.html">Aggregation Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/aggregate.html">aggregate</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/count.html">count</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/distinct.html">distinct</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/mapReduce.html">mapReduce</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-geospatial.html">Geospatial Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/geoSearch.html">geoSearch</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-crud.html">Query and Write Operation Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/delete.html">delete</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/find.html">find</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/findAndModify.html">findAndModify</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/getLastError.html">getLastError</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/getMore.html">getMore</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/insert.html">insert</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/resetError.html">resetError</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/update.html">update</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-plan-cache.html">Query Plan Cache Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/planCacheClear.html">planCacheClear</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/planCacheClearFilters.html">planCacheClearFilters</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/planCacheListFilters.html">planCacheListFilters</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/planCacheListPlans.html">planCacheListPlans</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/planCacheListQueryShapes.html">planCacheListQueryShapes</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/planCacheSetFilter.html">planCacheSetFilter</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-authentication.html">Authentication Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/authenticate.html">authenticate</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/getnonce.html">getnonce</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/logout.html">logout</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-user-management.html">User Management Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/createUser.html">createUser</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dropAllUsersFromDatabase.html">dropAllUsersFromDatabase</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dropUser.html">dropUser</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/grantRolesToUser.html">grantRolesToUser</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/revokeRolesFromUser.html">revokeRolesFromUser</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/updateUser.html">updateUser</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/usersInfo.html">usersInfo</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-role-management.html">Role Management Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/createRole.html">createRole</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dropRole.html">dropRole</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dropAllRolesFromDatabase.html">dropAllRolesFromDatabase</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/grantPrivilegesToRole.html">grantPrivilegesToRole</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/grantRolesToRole.html">grantRolesToRole</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/invalidateUserCache.html">invalidateUserCache</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/revokePrivilegesFromRole.html">revokePrivilegesFromRole</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/revokeRolesFromRole.html">revokeRolesFromRole</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/rolesInfo.html">rolesInfo</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/updateRole.html">updateRole</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-replication.html">Replication Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/applyOps.html">applyOps</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/isMaster.html">isMaster</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetAbortPrimaryCatchUp.html">replSetAbortPrimaryCatchUp</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetFreeze.html">replSetFreeze</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetGetConfig.html">replSetGetConfig</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetGetStatus.html">replSetGetStatus</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetInitiate.html">replSetInitiate</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetMaintenance.html">replSetMaintenance</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetReconfig.html">replSetReconfig</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetResizeOplog.html">replSetResizeOplog</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetStepDown.html">replSetStepDown</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/replSetSyncFrom.html">replSetSyncFrom</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-sharding.html">Sharding Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/addShard.html">addShard</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/addShardToZone.html">addShardToZone</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/balancerStart.html">balancerStart</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/balancerStatus.html">balancerStatus</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/balancerStop.html">balancerStop</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/checkShardingIndex.html">checkShardingIndex</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/clearJumboFlag.html">clearJumboFlag</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/cleanupOrphaned.html">cleanupOrphaned</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/enableSharding.html">enableSharding</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/flushRouterConfig.html">flushRouterConfig</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/getShardMap.html">getShardMap</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/getShardVersion.html">getShardVersion</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/isdbgrid.html">isdbgrid</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/listShards.html">listShards</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/medianKey.html">medianKey</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/moveChunk.html">moveChunk</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/movePrimary.html">movePrimary</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/mergeChunks.html">mergeChunks</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/removeShard.html">removeShard</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/removeShardFromZone.html">removeShardFromZone</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/setShardVersion.html">setShardVersion</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/shardCollection.html">shardCollection</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/shardingState.html">shardingState</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/split.html">split</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/splitChunk.html">splitChunk</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/splitVector.html">splitVector</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/unsetSharding.html">unsetSharding</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/updateZoneKeyRange.html">updateZoneKeyRange</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-sessions.html">Sessions Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/abortTransaction.html">abortTransaction</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/commitTransaction.html">commitTransaction</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/endSessions.html">endSessions</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/killAllSessions.html">killAllSessions</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/killAllSessionsByPattern.html">killAllSessionsByPattern</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/killSessions.html">killSessions</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/refreshSessions.html">refreshSessions</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/startSession.html">startSession</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-administration.html">Administration Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/clean.html">clean</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/cloneCollection.html">cloneCollection</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/cloneCollectionAsCapped.html">cloneCollectionAsCapped</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/collMod.html">collMod</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/compact.html">compact</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/connPoolSync.html">connPoolSync</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/convertToCapped.html">convertToCapped</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/create.html">create</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/createIndexes.html">createIndexes</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/currentOp.html">currentOp</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/drop.html">drop</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dropDatabase.html">dropDatabase</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dropConnections.html">dropConnections</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dropIndexes.html">dropIndexes</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/filemd5.html">filemd5</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/fsync.html">fsync</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/fsyncUnlock.html">fsyncUnlock</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/getParameter.html">getParameter</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/killCursors.html">killCursors</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/killOp.html">killOp</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/listCollections.html">listCollections</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/listDatabases.html">listDatabases</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/listIndexes.html">listIndexes</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/logRotate.html">logRotate</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/reIndex.html">reIndex</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/renameCollection.html">renameCollection</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/setFeatureCompatibilityVersion.html">setFeatureCompatibilityVersion</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/setParameter.html">setParameter</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/shutdown.html">shutdown</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-diagnostic.html">Diagnostic Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/availableQueryOptions.html">availableQueryOptions</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/buildInfo.html">buildInfo</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/collStats.html">collStats</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/connPoolStats.html">connPoolStats</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/connectionStatus.html">connectionStatus</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/cursorInfo.html">cursorInfo</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dataSize.html">dataSize</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dbHash.html">dbHash</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/dbStats.html">dbStats</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/diagLogging.html">diagLogging</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/driverOIDTest.html">driverOIDTest</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/explain.html">explain</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/features.html">features</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/getCmdLineOpts.html">getCmdLineOpts</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/getLog.html">getLog</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/hostInfo.html">hostInfo</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/isSelf.html">isSelf</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/listCommands.html">listCommands</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/netstat.html">netstat</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/ping.html">ping</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/profile.html">profile</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/serverStatus.html">serverStatus</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/shardConnPoolStats.html">shardConnPoolStats</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/top.html">top</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/validate.html">validate</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/whatsmyuri.html">whatsmyuri</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-free-monitoring.html">Free Monitoring Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/getFreeMonitoringStatus.html">getFreeMonitoringStatus</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/command/setFreeMonitoring.html">setFreeMonitoring</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/command/nav-auditing.html">System Events Auditing Commands</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/command/logApplicationMessage.html">logApplicationMessage</a></li></ul></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/method.html"><code class="docutils literal"><span class="pre">mongo</span></code> Shell Methods</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-collection.html">Collection Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.aggregate.html">db.collection.aggregate()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.bulkWrite.html">db.collection.bulkWrite()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.copyTo.html">db.collection.copyTo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.count.html">db.collection.count()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.countDocuments.html">db.collection.countDocuments()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.estimatedDocumentCount.html">db.collection.estimatedDocumentCount()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.createIndex.html">db.collection.createIndex()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.createIndexes.html">db.collection.createIndexes()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.dataSize.html">db.collection.dataSize()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.deleteOne.html">db.collection.deleteOne()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.deleteMany.html">db.collection.deleteMany()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.distinct.html">db.collection.distinct()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.drop.html">db.collection.drop()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.dropIndex.html">db.collection.dropIndex()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.dropIndexes.html">db.collection.dropIndexes()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.ensureIndex.html">db.collection.ensureIndex()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.explain.html">db.collection.explain()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.find.html">db.collection.find()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.findAndModify.html">db.collection.findAndModify()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.findOne.html">db.collection.findOne()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.findOneAndDelete.html">db.collection.findOneAndDelete()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.findOneAndReplace.html">db.collection.findOneAndReplace()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.findOneAndUpdate.html">db.collection.findOneAndUpdate()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.getIndexes.html">db.collection.getIndexes()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.getShardDistribution.html">db.collection.getShardDistribution()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.getShardVersion.html">db.collection.getShardVersion()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.insert.html">db.collection.insert()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.insertOne.html">db.collection.insertOne()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.insertMany.html">db.collection.insertMany()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.isCapped.html">db.collection.isCapped()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.latencyStats.html">db.collection.latencyStats()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.mapReduce.html">db.collection.mapReduce()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.reIndex.html">db.collection.reIndex()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.remove.html">db.collection.remove()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.renameCollection.html">db.collection.renameCollection()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.replaceOne.html">db.collection.replaceOne()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.save.html">db.collection.save()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.stats.html">db.collection.stats()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.storageSize.html">db.collection.storageSize()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.totalIndexSize.html">db.collection.totalIndexSize()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.totalSize.html">db.collection.totalSize()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.update.html">db.collection.update()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.updateOne.html">db.collection.updateOne()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.updateMany.html">db.collection.updateMany()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.watch.html">db.collection.watch()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.validate.html">db.collection.validate()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-cursor.html">Cursor Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.addOption.html">cursor.addOption()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.allowPartialResults.html">cursor.allowPartialResults()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.batchSize.html">cursor.batchSize()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.close.html">cursor.close()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.isClosed.html">cursor.isClosed()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.collation.html">cursor.collation()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.comment.html">cursor.comment()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.count.html">cursor.count()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.explain.html">cursor.explain()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.forEach.html">cursor.forEach()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.hasNext.html">cursor.hasNext()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.hint.html">cursor.hint()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.isExhausted.html">cursor.isExhausted()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.itcount.html">cursor.itcount()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.limit.html">cursor.limit()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.map.html">cursor.map()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.max.html">cursor.max()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.maxTimeMS.html">cursor.maxTimeMS()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.min.html">cursor.min()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.next.html">cursor.next()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.noCursorTimeout.html">cursor.noCursorTimeout()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.objsLeftInBatch.html">cursor.objsLeftInBatch()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.pretty.html">cursor.pretty()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.readConcern.html">cursor.readConcern()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.readPref.html">cursor.readPref()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.returnKey.html">cursor.returnKey()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.showRecordId.html">cursor.showRecordId()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.size.html">cursor.size()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.skip.html">cursor.skip()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.sort.html">cursor.sort()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.tailable.html">cursor.tailable()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cursor.toArray.html">cursor.toArray()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-database.html">Database Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.adminCommand.html">db.adminCommand()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.aggregate.html">db.aggregate()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.cloneCollection.html">db.cloneCollection()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.cloneDatabase.html">db.cloneDatabase()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.commandHelp.html">db.commandHelp()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.copyDatabase.html">db.copyDatabase()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.createCollection.html">db.createCollection()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.createView.html">db.createView()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.currentOp.html">db.currentOp()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.dropDatabase.html">db.dropDatabase()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.eval.html">db.eval()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.fsyncLock.html">db.fsyncLock()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.fsyncUnlock.html">db.fsyncUnlock()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getCollection.html">db.getCollection()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getCollectionInfos.html">db.getCollectionInfos()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getCollectionNames.html">db.getCollectionNames()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getLastError.html">db.getLastError()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getLastErrorObj.html">db.getLastErrorObj()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getLogComponents.html">db.getLogComponents()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getMongo.html">db.getMongo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getName.html">db.getName()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getProfilingLevel.html">db.getProfilingLevel()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getProfilingStatus.html">db.getProfilingStatus()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getReplicationInfo.html">db.getReplicationInfo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getSiblingDB.html">db.getSiblingDB()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.help.html">db.help()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.hostInfo.html">db.hostInfo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.isMaster.html">db.isMaster()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.killOp.html">db.killOp()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.listCommands.html">db.listCommands()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.logout.html">db.logout()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.printCollectionStats.html">db.printCollectionStats()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.printReplicationInfo.html">db.printReplicationInfo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.printShardingStatus.html">db.printShardingStatus()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.printSlaveReplicationInfo.html">db.printSlaveReplicationInfo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.resetError.html">db.resetError()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.runCommand.html">db.runCommand()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.serverBuildInfo.html">db.serverBuildInfo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.serverCmdLineOpts.html">db.serverCmdLineOpts()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.serverStatus.html">db.serverStatus()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.setLogLevel.html">db.setLogLevel()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.setProfilingLevel.html">db.setProfilingLevel()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.shutdownServer.html">db.shutdownServer()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.stats.html">db.stats()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.version.html">db.version()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.watch.html">db.watch()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-plan-cache.html">Query Plan Cache Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.getPlanCache.html">db.collection.getPlanCache()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/PlanCache.clear.html">PlanCache.clear()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/PlanCache.clearPlansByQuery.html">PlanCache.clearPlansByQuery()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/PlanCache.getPlansByQuery.html">PlanCache.getPlansByQuery()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/PlanCache.help.html">PlanCache.help()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/PlanCache.listQueryShapes.html">PlanCache.listQueryShapes()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-bulk.html">Bulk Operation Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.initializeOrderedBulkOp.html">db.collection.initializeOrderedBulkOp()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.collection.initializeUnorderedBulkOp.html">db.collection.initializeUnorderedBulkOp()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.html">Bulk()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.execute.html">Bulk.execute()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.html">Bulk.find()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.arrayFilters.html">Bulk.find.arrayFilters()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.collation.html">Bulk.find.collation()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.hint.html">Bulk.find.hint()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.remove.html">Bulk.find.remove()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.removeOne.html">Bulk.find.removeOne()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.replaceOne.html">Bulk.find.replaceOne()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.updateOne.html">Bulk.find.updateOne()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.update.html">Bulk.find.update()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.find.upsert.html">Bulk.find.upsert()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.getOperations.html">Bulk.getOperations()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.insert.html">Bulk.insert()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.tojson.html">Bulk.tojson()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Bulk.toString.html">Bulk.toString()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-user-management.html">User Management Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.auth.html">db.auth()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.changeUserPassword.html">db.changeUserPassword()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.createUser.html">db.createUser()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.dropUser.html">db.dropUser()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.dropAllUsers.html">db.dropAllUsers()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getUser.html">db.getUser()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getUsers.html">db.getUsers()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.grantRolesToUser.html">db.grantRolesToUser()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.removeUser.html">db.removeUser()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.revokeRolesFromUser.html">db.revokeRolesFromUser()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.updateUser.html">db.updateUser()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/passwordPrompt.html">passwordPrompt()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-role-management.html">Role Management Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.createRole.html">db.createRole()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.dropRole.html">db.dropRole()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.dropAllRoles.html">db.dropAllRoles()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getRole.html">db.getRole()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getRoles.html">db.getRoles()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.grantPrivilegesToRole.html">db.grantPrivilegesToRole()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.revokePrivilegesFromRole.html">db.revokePrivilegesFromRole()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.grantRolesToRole.html">db.grantRolesToRole()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.revokeRolesFromRole.html">db.revokeRolesFromRole()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.updateRole.html">db.updateRole()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-replication.html">Replication Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.add.html">rs.add()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.addArb.html">rs.addArb()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.conf.html">rs.conf()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.freeze.html">rs.freeze()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.help.html">rs.help()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.initiate.html">rs.initiate()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.printReplicationInfo.html">rs.printReplicationInfo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.printSlaveReplicationInfo.html">rs.printSlaveReplicationInfo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.reconfig.html">rs.reconfig()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.remove.html">rs.remove()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.slaveOk.html">rs.slaveOk()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.status.html">rs.status()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.stepDown.html">rs.stepDown()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rs.syncFrom.html">rs.syncFrom()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-sharding.html">Sharding Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.addShard.html">sh.addShard()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.addShardTag.html">sh.addShardTag()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.addShardToZone.html">sh.addShardToZone()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.addTagRange.html">sh.addTagRange()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.disableBalancing.html">sh.disableBalancing()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.enableBalancing.html">sh.enableBalancing()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.disableAutoSplit.html">sh.disableAutoSplit</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.enableAutoSplit.html">sh.enableAutoSplit</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.enableSharding.html">sh.enableSharding()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.getBalancerHost.html">sh.getBalancerHost()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.getBalancerState.html">sh.getBalancerState()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.removeTagRange.html">sh.removeTagRange()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.removeRangeFromZone.html">sh.removeRangeFromZone()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.help.html">sh.help()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.isBalancerRunning.html">sh.isBalancerRunning()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.moveChunk.html">sh.moveChunk()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.removeShardTag.html">sh.removeShardTag()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.removeShardFromZone.html">sh.removeShardFromZone()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.setBalancerState.html">sh.setBalancerState()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.shardCollection.html">sh.shardCollection()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.splitAt.html">sh.splitAt()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.splitFind.html">sh.splitFind()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.startBalancer.html">sh.startBalancer()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.status.html">sh.status()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.stopBalancer.html">sh.stopBalancer()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.waitForBalancer.html">sh.waitForBalancer()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.waitForBalancerOff.html">sh.waitForBalancerOff()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.waitForPingChange.html">sh.waitForPingChange()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sh.updateZoneKeyRange.html">sh.updateZoneKeyRange()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/convertShardKeyToHashed.html">convertShardKeyToHashed</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-free-monitoring.html">Free Monitoring Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.disableFreeMonitoring.html">db.disableFreeMonitoring()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.enableFreeMonitoring.html">db.enableFreeMonitoring()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/db.getFreeMonitoringStatus.html">db.getFreeMonitoringStatus</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-constructor.html">Object Constructors and Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/BulkWriteResult.html">BulkWriteResult()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Date.html">Date()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/ObjectId.html">ObjectId</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/ObjectId.getTimestamp.html">ObjectId.getTimestamp()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/ObjectId.toString.html">ObjectId.toString()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/ObjectId.valueOf.html">ObjectId.valueOf()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/UUID.html">UUID()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/WriteResult.html">WriteResult()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/WriteResult.hasWriteError.html">WriteResult.hasWriteError()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/WriteResult.hasWriteConcernError.html">WriteResult.hasWriteConcernError()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-connection.html">Connection Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/connect.html">connect()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.html">Mongo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.getDB.html">Mongo.getDB()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.getReadPrefMode.html">Mongo.getReadPrefMode()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.getReadPrefTagSet.html">Mongo.getReadPrefTagSet()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.isCausalConsistency.html">Mongo.isCausalConsistency()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.setCausalConsistency.html">Mongo.setCausalConsistency()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.setReadPref.html">Mongo.setReadPref()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.setSlaveOk.html">Mongo.setSlaveOk()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.startSession.html">Mongo.startSession()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Mongo.watch.html">Mongo.watch()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/Session.html">Session</a><ul><li class="toctree-l5"><a class="reference internal" href="../reference/method/Session.abortTransaction.html">Session.abortTransaction()</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/method/Session.commitTransaction.html">Session.commitTransaction()</a></li><li class="toctree-l5"><a class="reference internal" href="../reference/method/Session.startTransaction.html">Session.startTransaction()</a></li></ul></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/SessionOptions.html">SessionOptions</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-native.html">Native Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/cat.html">cat()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/cd.html">cd()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/copyDbpath.html">copyDbpath()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/getHostName.html">getHostName()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/getMemInfo.html">getMemInfo()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/hostname.html">hostname()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/isInteractive.html">isInteractive()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/listFiles.html">listFiles()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/load.html">load()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/ls.html">ls()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/md5sumFile.html">md5sumFile()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/mkdir.html">mkdir()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/pwd.html">pwd()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/quit.html">quit()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/removeFile.html">removeFile()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/resetDbpath.html">resetDbpath()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/sleep.html">sleep()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/setVerboseShell.html">setVerboseShell()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/version.html">version()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/isWindows.html">_isWindows()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/rand.html">_rand()</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="../reference/method/js-client-side-field-level-encryption.html">Client-Side Field Level Encryption Methods</a><ul><li class="toctree-l4"><a class="reference internal" href="../reference/method/getKeyVault.html">getKeyVault()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/KeyVault.createKey.html">KeyVault.createKey()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/KeyVault.deleteKey.html">KeyVault.deleteKey()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/KeyVault.getKey.html">KeyVault.getKey()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/KeyVault.getKeys.html">KeyVault.getKeys()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/KeyVault.addKeyAlternateName.html">KeyVault.addKeyAlternateName()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/KeyVault.removeKeyAlternateName.html">KeyVault.removeKeyAlternateName()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/KeyVault.getKeyByAltName.html">KeyVault.getKeyByAltName()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/getClientEncryption.html">getClientEncryption()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/ClientEncryption.encrypt.html">ClientEncryption.encrypt()</a></li><li class="toctree-l4"><a class="reference internal" href="../reference/method/ClientEncryption.decrypt.html">ClientEncryption.decrypt()</a></li></ul></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/program.html">MongoDB Package Components</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongod.html"><code class="docutils literal"><span class="pre">mongod</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongos.html"><code class="docutils literal"><span class="pre">mongos</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongo.html"><code class="docutils literal"><span class="pre">mongo</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongod.exe.html"><code class="docutils literal"><span class="pre">mongod.exe</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongos.exe.html"><code class="docutils literal"><span class="pre">mongos.exe</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongodump.html"><code class="docutils literal"><span class="pre">mongodump</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongorestore.html"><code class="docutils literal"><span class="pre">mongorestore</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/bsondump.html"><code class="docutils literal"><span class="pre">bsondump</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongoimport.html"><code class="docutils literal"><span class="pre">mongoimport</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongoexport.html"><code class="docutils literal"><span class="pre">mongoexport</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongostat.html"><code class="docutils literal"><span class="pre">mongostat</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongotop.html"><code class="docutils literal"><span class="pre">mongotop</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongoreplay.html"><code class="docutils literal"><span class="pre">mongoreplay</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongoldap.html"><code class="docutils literal"><span class="pre">mongoldap</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/mongofiles.html"><code class="docutils literal"><span class="pre">mongofiles</span></code></a></li><li class="toctree-l3"><a class="reference internal" href="../reference/program/install_compass.html"><code class="docutils literal"><span class="pre">install_compass</span></code></a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/configuration-options.html">Configuration File Options</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/expansion-directives.html">Externally Sourced Configuration File Values</a></li><li class="toctree-l3"><a class="reference internal" href="../tutorial/convert-command-line-options-to-yaml.html">Convert Command-Line Options to YAML</a></li><li class="toctree-l3"><a class="reference internal" href="../reference/configuration-file-settings-command-line-options-mapping.html">Configuration File Settings and Command-Line Options Mapping</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/parameters.html">MongoDB Server Parameters</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/limits.html">MongoDB Limits and Thresholds</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/explain-results.html">Explain Results</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/system-collections.html">System Collections</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/connection-string.html">Connection String URI Format</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/collation.html">Collation</a><ul><li class="toctree-l3"><a class="reference internal" href="../reference/collation-locales-defaults.html">Collation Locales and Default Parameters</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="../reference/mongodb-wire-protocol.html">MongoDB Wire Protocol</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/log-messages.html">Log Messages</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/exit-codes.html">Exit Codes and Statuses</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/glossary.html">Glossary</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/default-mongodb-port.html">Default MongoDB Port</a></li><li class="toctree-l2"><a class="reference internal" href="../reference/server-sessions.html">Server Sessions</a></li></ul></li><li class="toctree-l1 current"><a class="reference internal" href="../release-notes.html">Release Notes</a><ul class="current"><li class="toctree-l2"><a class="reference internal" href="4.2.html">Release Notes for MongoDB 4.2</a><ul><li class="toctree-l3"><a class="reference internal" href="4.2-compatibility.html">Compatibility Changes in MongoDB 4.2</a></li><li class="toctree-l3"><a class="reference internal" href="4.2-upgrade-standalone.html">Upgrade a Standalone to 4.2</a></li><li class="toctree-l3"><a class="reference internal" href="4.2-upgrade-replica-set.html">Upgrade a Replica Set to 4.2</a></li><li class="toctree-l3"><a class="reference internal" href="4.2-upgrade-sharded-cluster.html">Upgrade a Sharded Cluster to 4.2</a></li><li class="toctree-l3"><a class="reference internal" href="4.2-downgrade.html">Downgrade 4.2 to 4.0</a><ul><li class="toctree-l4"><a class="reference internal" href="4.2-downgrade-standalone.html">Downgrade 4.2 Standalone to 4.0</a></li><li class="toctree-l4"><a class="reference internal" href="4.2-downgrade-replica-set.html">Downgrade 4.2 Replica Set to 4.0</a></li><li class="toctree-l4"><a class="reference internal" href="4.2-downgrade-sharded-cluster.html">Downgrade 4.2 Sharded Cluster to 4.0</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="4.2-changelog.html">4.2 Changelog</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="4.0.html">Release Notes for MongoDB 4.0</a><ul><li class="toctree-l3"><a class="reference internal" href="4.0-compatibility.html">Compatibility Changes in MongoDB 4.0</a></li><li class="toctree-l3"><a class="reference internal" href="4.0-upgrade-standalone.html">Upgrade a Standalone to 4.0</a></li><li class="toctree-l3"><a class="reference internal" href="4.0-upgrade-replica-set.html">Upgrade a Replica Set to 4.0</a></li><li class="toctree-l3"><a class="reference internal" href="4.0-upgrade-sharded-cluster.html">Upgrade a Sharded Cluster to 4.0</a></li><li class="toctree-l3"><a class="reference internal" href="4.0-downgrade-standalone.html">Downgrade 4.0 Standalone to 3.6</a></li><li class="toctree-l3"><a class="reference internal" href="4.0-downgrade-replica-set.html">Downgrade 4.0 Replica Set to 3.6</a></li><li class="toctree-l3"><a class="reference internal" href="4.0-downgrade-sharded-cluster.html">Downgrade 4.0 Sharded Cluster to 3.6</a></li><li class="toctree-l3"><a class="reference internal" href="4.0-changelog.html">4.0 Changelog</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="3.6.html">Release Notes for MongoDB 3.6</a><ul><li class="toctree-l3"><a class="reference internal" href="3.6-changelog.html">3.6 Changelog</a></li><li class="toctree-l3"><a class="reference internal" href="3.6-compatibility.html">Compatibility Changes in MongoDB 3.6</a></li><li class="toctree-l3"><a class="reference internal" href="3.6-upgrade-standalone.html">Upgrade a Standalone to 3.6</a></li><li class="toctree-l3"><a class="reference internal" href="3.6-upgrade-replica-set.html">Upgrade a Replica Set to 3.6</a></li><li class="toctree-l3"><a class="reference internal" href="3.6-upgrade-sharded-cluster.html">Upgrade a Sharded Cluster to 3.6</a></li><li class="toctree-l3"><a class="reference internal" href="3.6-downgrade-standalone.html">Downgrade 3.6 Standalone to 3.4</a></li><li class="toctree-l3"><a class="reference internal" href="3.6-downgrade-replica-set.html">Downgrade 3.6 Replica Set to 3.4</a></li><li class="toctree-l3"><a class="reference internal" href="3.6-downgrade-sharded-cluster.html">Downgrade 3.6 Sharded Cluster to 3.4</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="3.4.html">Release Notes for MongoDB 3.4</a><ul><li class="toctree-l3"><a class="reference internal" href="3.4-changelog.html">3.4 Changelog</a></li><li class="toctree-l3"><a class="reference internal" href="3.4-compatibility.html">Compatibility Changes in MongoDB 3.4</a></li><li class="toctree-l3"><a class="reference internal" href="3.4-upgrade-standalone.html">Upgrade a Standalone to 3.4</a></li><li class="toctree-l3"><a class="reference internal" href="3.4-upgrade-replica-set.html">Upgrade a Replica Set to 3.4</a></li><li class="toctree-l3"><a class="reference internal" href="3.4-upgrade-sharded-cluster.html">Upgrade a Sharded Cluster to 3.4</a></li><li class="toctree-l3"><a class="reference internal" href="3.4-downgrade.html">Downgrade MongoDB 3.4 to 3.2</a><ul><li class="toctree-l4"><a class="reference internal" href="3.4-downgrade-standalone.html">Downgrade 3.4 Standalone to 3.2</a></li><li class="toctree-l4"><a class="reference internal" href="3.4-downgrade-replica-set.html">Downgrade 3.4 Replica Set to 3.2</a></li><li class="toctree-l4"><a class="reference internal" href="3.4-downgrade-sharded-cluster.html">Downgrade 3.4 Sharded Cluster to 3.2</a></li></ul></li></ul></li><li class="toctree-l2 current"><a class="reference internal current" href="">Release Notes for MongoDB 3.2</a><ul><li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html">3.2 Changelog</a></li><li class="toctree-l3"><a class="reference internal" href="3.2-compatibility.html">Compatibility Changes in MongoDB 3.2</a><ul><li class="toctree-l4"><a class="reference internal" href="3.2-javascript.html">JavaScript Changes in MongoDB 3.2</a></li></ul></li><li class="toctree-l3"><a class="reference internal" href="3.2-upgrade.html">Upgrade MongoDB to 3.2</a></li><li class="toctree-l3"><a class="reference internal" href="3.2-downgrade.html">Downgrade MongoDB from 3.2</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="3.0.html">Release Notes for MongoDB 3.0</a><ul><li class="toctree-l3"><a class="reference internal" href="3.0-changelog.html">3.0 Changelog</a></li><li class="toctree-l3"><a class="reference internal" href="3.0-compatibility.html">Compatibility Changes in MongoDB 3.0</a></li><li class="toctree-l3"><a class="reference internal" href="3.0-upgrade.html">Upgrade MongoDB to 3.0</a></li><li class="toctree-l3"><a class="reference internal" href="3.0-scram.html">Upgrade to SCRAM</a></li><li class="toctree-l3"><a class="reference internal" href="3.0-downgrade.html">Downgrade MongoDB from 3.0</a></li></ul></li><li class="toctree-l2"><a class="reference internal" href="2.6.html">Release Notes for MongoDB 2.6</a><ul><li class="toctree-l3"><a class="reference internal" href="2.6-changelog.html">2.6 Changelog</a></li><li class="toctree-l3"><a class="reference internal" href="2.6-compatibility.html">Compatibility Changes in MongoDB 2.6</a></li><li class="toctree-l3"><a class="reference internal" href="2.6-upgrade.html">Upgrade MongoDB to 2.6</a></li><li class="toctree-l3"><a class="reference internal" href="2.6-upgrade-authorization.html">Upgrade User Authorization Data to 2.6 Format</a></li><li class="toctree-l3"><a class="reference internal" href="2.6-downgrade.html">Downgrade MongoDB from 2.6</a></li></ul></li><li 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                  <div class="section" id="release-notes-for-mongodb-3-2">
<h1>Release Notes for MongoDB 3.2<a class="headerlink" href="#release-notes-for-mongodb-3-2" title="Permalink to this headline">¶</a></h1>
<div class="contents twocols local topic" id="on-this-page">
<p class="topic-title first">On this page</p>
<ul class="simple">
<li><a class="reference internal" href="#minor-releases" id="id24">Minor Releases</a></li>
<li><a class="reference internal" href="#wiredtiger-as-default" id="id25">WiredTiger as Default</a></li>
<li><a class="reference internal" href="#replication-election-enhancements" id="id26">Replication Election Enhancements</a></li>
<li><a class="reference internal" href="#sharded-cluster-enhancements" id="id27">Sharded Cluster Enhancements</a></li>
<li><a class="reference internal" href="#readconcern" id="id28"><code class="docutils literal"><span class="pre">readConcern</span></code></a></li>
<li><a class="reference internal" href="#partial-indexes" id="id29">Partial Indexes</a></li>
<li><a class="reference internal" href="#document-validation" id="id30">Document Validation</a></li>
<li><a class="reference internal" href="#aggregation-framework-enhancements" id="id31">Aggregation Framework Enhancements</a></li>
<li><a class="reference internal" href="#mongodb-tools-enhancements" id="id32">MongoDB Tools Enhancements</a></li>
<li><a class="reference internal" href="#encrypted-storage-engine" id="id33">Encrypted Storage Engine</a></li>
<li><a class="reference internal" href="#text-search-enhancements" id="id34">Text Search Enhancements</a></li>
<li><a class="reference internal" href="#new-storage-engines" id="id35">New Storage Engines</a></li>
<li><a class="reference internal" href="#id21" id="id36">General Enhancements</a></li>
<li><a class="reference internal" href="#changes-affecting-compatibility" id="id37">Changes Affecting Compatibility</a></li>
<li><a class="reference internal" href="#upgrade-process" id="id38">Upgrade Process</a></li>
<li><a class="reference internal" href="#known-issues-in-3-2-1" id="id39">Known Issues in 3.2.1</a></li>
<li><a class="reference internal" href="#known-issues-in-3-2-0" id="id40">Known Issues in 3.2.0</a></li>
<li><a class="reference internal" href="#download" id="id41">Download</a></li>
</ul>
</div>
<p><em>Dec 8, 2015</em></p>
<p>MongoDB 3.2 is now available. Key features include WiredTiger as the
default storage engine, replication election enhancements, config
servers as replica sets, <code class="docutils literal"><span class="pre">readConcern</span></code>, and document validations.</p>
<p>OpsManager 2.0 is also available. See the <a class="reference external" href="http://docs.opsmanager.mongodb.com/current/">Ops Manager documentation</a> and the <a class="reference external" href="http://docs.opsmanager.mongodb.com/current/release-notes/application/">Ops Manager
release notes</a>
for more information.</p>
<div class="section" id="minor-releases">
<h2>Minor Releases<a class="headerlink" href="#minor-releases" title="Permalink to this headline">¶</a></h2>
<div class="toctree-wrapper hidden compound">
<ul>
<li class="toctree-l1"><a class="reference internal" href="3.2-changelog.html">3.2 Changelog</a><ul>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id1">3.2.22 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#replication">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#internals">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id3">3.2.21 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#query">Query</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#storage">Storage</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#operations">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#build-and-packaging">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id5">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id6">3.2.20 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#security">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id8">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id9">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id10">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id11">3.2.19 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#sharding">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id13">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id14">Query</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#write-operations">Write Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id15">Storage</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id16">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id17">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id18">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id19">3.2.18 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id21">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#aggregation">Aggregation</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#javascript">JavaScript</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id22">Storage</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id23">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id24">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id25">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id26">3.2.17 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id28">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id29">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id30">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id31">JavaScript</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id32">Storage</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id33">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id34">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id35">3.2.16 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id37">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id38">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id39">3.2.15 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id41">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id42">JavaScript</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id43">Storage</a><ul>
<li class="toctree-l4"><a class="reference internal" href="3.2-changelog.html#wiredtiger">WiredTiger</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id44">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id45">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id46">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id47">3.2.14 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id49">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id50">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id51">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id52">JavaScript</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id53">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id54">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id55">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id56">3.2.13 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id58">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id59">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id60">Query</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id61">Aggregation</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id62">JavaScript</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id63">Storage</a><ul>
<li class="toctree-l4"><a class="reference internal" href="3.2-changelog.html#id64">WiredTiger</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-changelog.html#mmap">MMAP</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#ttl">TTL</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id65">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id66">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id67">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id68">3.2.12 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id70">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id71">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id72">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id73">Query</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id74">Write Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id75">Aggregation</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id76">JavaScript</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id77">Storage</a><ul>
<li class="toctree-l4"><a class="reference internal" href="3.2-changelog.html#id78">WiredTiger</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id79">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id80">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id81">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id82">3.2.11 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id84">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id85">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id86">Aggregation</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id87">Storage</a><ul>
<li class="toctree-l4"><a class="reference internal" href="3.2-changelog.html#id88">WiredTiger</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id89">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id90">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id91">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id92">3.2.10 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id94">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id95">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id96">Query</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id97">Write Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id98">Aggregation</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id99">JavaScript</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id100">WiredTiger</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#gridfs">GridFS</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id101">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id102">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#tools">Tools</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id103">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id104">3.2.9 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id106">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id107">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id108">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id109">Query</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id110">Storage</a><ul>
<li class="toctree-l4"><a class="reference internal" href="3.2-changelog.html#id111">WiredTiger</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id112">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id113">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id114">Tools</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id115">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id116">3.2.8 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id118">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id119">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id120">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id121">Query</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id122">Write Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id123">JavaScript</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id124">Storage</a><ul>
<li class="toctree-l4"><a class="reference internal" href="3.2-changelog.html#id125">WiredTiger</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-changelog.html#id126">MMAP</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id127">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id128">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id129">Tools</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id130">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id131">3.2.7 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id133">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id134">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id135">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id136">Query</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id137">Storage</a><ul>
<li class="toctree-l4"><a class="reference internal" href="3.2-changelog.html#id138">WiredTiger</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id139">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id140">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id141">Tools</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id142">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id143">3.2.6 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id145">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id146">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id147">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id148">Query</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id149">JavaScript</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id150">Storage</a><ul>
<li class="toctree-l4"><a class="reference internal" href="3.2-changelog.html#id151">WiredTiger</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id152">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id153">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id154">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id155">3.2.5 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id157">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id158">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id159">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id160">Query</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id161">Write Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id162">Aggregation</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id163">Storage</a><ul>
<li class="toctree-l4"><a class="reference internal" href="3.2-changelog.html#id164">WiredTiger</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id165">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id166">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id167">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id168">3.2.4 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id170">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id171">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id172">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id173">Query</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id174">Aggregation</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id175">JavaScript</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id176">Storage</a><ul>
<li class="toctree-l4"><a class="reference internal" href="3.2-changelog.html#id177">WiredTiger</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id178">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id179">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id180">Tools</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id181">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id182">3.2.3 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id184">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id185">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id186">Query</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id187">Write Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id188">Aggregation</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id189">JavaScript</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id190">Storage</a><ul>
<li class="toctree-l4"><a class="reference internal" href="3.2-changelog.html#id191">WiredTiger</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-changelog.html#id192">MMAP</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id193">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id194">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id195">Tools</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id196">Internals</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-changelog.html#id197">3.2.1 Changelog</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id199">Security</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id200">Sharding</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id201">Replication</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id202">Query</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id203">Storage</a><ul>
<li class="toctree-l4"><a class="reference internal" href="3.2-changelog.html#id204">WiredTiger</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id205">Operations</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id206">Build and Packaging</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id207">Tools</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-changelog.html#id208">Internals</a></li>
</ul>
</li>
</ul>
</li>
</ul>
</div>
<div class="section" id="dec-28-2018">
<span id="release-notes"></span><h3>3.2.22 - Dec 28, 2018<a class="headerlink" href="#dec-28-2018" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-38425">SERVER-38425</a> Oplog Visibility Query is a collection scan in 3.2.21</li>
<li><a class="reference internal" href="3.2-changelog.html#id1"><span class="std std-ref">3.2.22 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2CTOOLS%2CWT)%20AND%20resolution%3D%27Fixed%27%20and%20fixversion%3D%273.2.22%27">All JIRA issues closed in 3.2.22</a></li>
</ul>
</div>
<div class="section" id="sep-7-2018">
<span id="id1"></span><h3>3.2.21 - Sep 7, 2018<a class="headerlink" href="#sep-7-2018" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-32999">SERVER-32999</a>: Platform Support: remove Debian 7.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-36010">SERVER-36010</a> Change log messages for Windows stacktraces to use error() or severe() rather than log().</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-30724">SERVER-30724</a> Initial sync might miss ops that were in flight when it started.</li>
<li><a class="reference internal" href="3.2-changelog.html#id3"><span class="std std-ref">3.2.21 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2CTOOLS%2CWT)%20AND%20resolution%3D%27Fixed%27%20and%20fixversion%3D%273.2.21%27">All JIRA issues closed in 3.2.21</a></li>
</ul>
</div>
<div class="section" id="may-10-2018">
<span id="id2"></span><h3>3.2.20 - May 10, 2018<a class="headerlink" href="#may-10-2018" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-32241">SERVER-32241</a>: applyOps reports success even when a nested
applyOps fails.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-32923">SERVER-32923</a>: Platform Support: remove SLES11 builds.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-31535">SERVER-31535</a>: Platform Support: remove Ubuntu 12.04 builds.</li>
<li><a class="reference internal" href="3.2-changelog.html#id6"><span class="std std-ref">3.2.20 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2CTOOLS%2CWT)%20AND%20resolution%3D%27Fixed%27%20and%20fixversion%3D%273.2.20%27">All JIRA issues closed in 3.2.20</a></li>
</ul>
</div>
<div class="section" id="feb-6-2018">
<span id="id3"></span><h3>3.2.19 - Feb 6, 2018<a class="headerlink" href="#feb-6-2018" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-30189">SERVER-30189</a>: Reduce calls to allocator for large $in expressions</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-30853">SERVER-30853</a>: Update Mongod init scripts to set unlimited locked memory</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-32001">SERVER-32001</a>: Unindexing a key in a partial unique index may cause server crash</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-32048">SERVER-32048</a>: Updates using a numeric path component may cause index entries not to be created</li>
<li><a class="reference internal" href="3.2-changelog.html#id11"><span class="std std-ref">3.2.19 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2CTOOLS%2CWT)%20AND%20resolution%3D%27Fixed%27%20and%20fixversion%3D%273.2.19%27">All JIRA issues closed in 3.2.19</a></li>
</ul>
</div>
<div class="section" id="nov-29-2017">
<span id="id4"></span><h3>3.2.18 - Nov 29, 2017<a class="headerlink" href="#nov-29-2017" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-29287">SERVER-29287</a>: Upgrade pcre to 8.41</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-31101">SERVER-31101</a>: WT table not dropped after collection is dropped due to long-running OperationContext</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-31149">SERVER-31149</a>: Enable recovery progress messages</li>
<li><a class="reference internal" href="3.2-changelog.html#id19"><span class="std std-ref">3.2.18 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2CTOOLS%2CWT)%20AND%20resolution%3D%27Fixed%27%20and%20fixversion%3D%273.2.18%27">All JIRA issues closed in 3.2.18</a></li>
</ul>
</div>
<div class="section" id="sept-28-2017">
<span id="id5"></span><h3>3.2.17 - Sept 28, 2017<a class="headerlink" href="#sept-28-2017" title="Permalink to this headline">¶</a></h3>
<p>Issues fixed:</p>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-30636">SERVER-30636</a>: RangeDeleter assert failed because of replication lag</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-30943">SERVER-30943</a>: Segmentation fault on attempt to access an invalidated BSON Object in JS scope</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/WT-3327">WT-3327</a>: Checkpoints can hang if time runs backward</li>
<li><a class="reference internal" href="3.2-changelog.html#id26"><span class="std std-ref">3.2.17 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2CTOOLS%2CWT)%20AND%20resolution%3D%27Fixed%27%20and%20fixversion%3D%273.2.17%27">All JIRA issues closed in 3.2.17</a></li>
</ul>
</div>
<div class="section" id="jul-27-2017">
<span id="id6"></span><h3>3.2.16 - Jul 27, 2017<a class="headerlink" href="#jul-27-2017" title="Permalink to this headline">¶</a></h3>
<p>Issues fixed:</p>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-26952">SERVER-26952</a>: Cache SCRAM-SHA-1 ClientKey</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-28578">SERVER-28578</a>: When doing an upgrade from PV0 to PV1, we should not return from the reconfigure until the lastVote document is written.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-29568">SERVER-29568</a>: Enable configuration of OpenSSL cipher suite via setParameter</li>
<li><a class="reference internal" href="3.2-changelog.html#id35"><span class="std std-ref">3.2.16 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2CTOOLS%2CWT)%20AND%20resolution%3D%27Fixed%27%20and%20fixversion%3D%273.2.16%27">All JIRA issues closed in 3.2.16</a></li>
</ul>
</div>
<div class="section" id="jul-5-2017">
<span id="id7"></span><h3>3.2.15 - Jul 5, 2017<a class="headerlink" href="#jul-5-2017" title="Permalink to this headline">¶</a></h3>
<p>Issues fixed:</p>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-29237">SERVER-29237</a>:  Add ShardingTaskExecutorPoolMaxConnecting flag for <a class="reference internal" href="../reference/program/mongos.html#bin.mongos" title="bin.mongos"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongos</span></code></a>.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-29850">SERVER-29850</a>:  Access violation due to a bug in internal page splitting in WiredTiger.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/WT-3362">WT-3362</a>:  Cursor opens should never block for the duration of a checkpoint.</li>
<li><a class="reference internal" href="3.2-changelog.html#id39"><span class="std std-ref">3.2.15 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2CTOOLS%2CWT)%20AND%20resolution%3D%27Fixed%27%20and%20fixversion%3D%273.2.15%27">All JIRA issues closed in 3.2.15</a></li>
</ul>
</div>
<div class="section" id="jun-13-2017">
<span id="id8"></span><h3>3.2.14 -Jun 13, 2017<a class="headerlink" href="#jun-13-2017" title="Permalink to this headline">¶</a></h3>
<p>Issues fixed:</p>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-26452">SERVER-26452</a>: <code class="docutils literal"><span class="pre">renameCollection</span></code> should handle write conflicts.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-29365">SERVER-29365</a>: No-op <code class="docutils literal"><span class="pre">applyOps</span></code> does not wait for majority writeConcern before returning.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-28014">SERVER-28014</a>: When ssl mode is <code class="docutils literal"><span class="pre">preferSSL</span></code>, should log
connections that do not use SSL.</li>
<li><a class="reference internal" href="3.2-changelog.html#id47"><span class="std std-ref">3.2.14 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2CTOOLS%2CWT)%20AND%20resolution%3D%27Fixed%27%20and%20fixversion%3D%273.2.14%27">All JIRA issues closed in 3.2.14</a></li>
</ul>
</div>
<div class="section" id="may-1-2017">
<span id="id9"></span><h3>3.2.13 – May 1, 2017<a class="headerlink" href="#may-1-2017" title="Permalink to this headline">¶</a></h3>
<p>Issues fixed:</p>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-3181">SERVER-3181</a>: Add <code class="docutils literal"><span class="pre">nameOnly</span></code> option to listDatabases to
only get db names, not size info.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21818">SERVER-21818</a>: Capture system metrics in FTDC</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-25318">SERVER-25318</a>: Limit total memory utilization for bulk index builds</li>
<li><a class="reference internal" href="3.2-changelog.html#id56"><span class="std std-ref">3.2.13 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2CTOOLS%2CWT)%20AND%20resolution%3D%27Fixed%27%20and%20fixversion%3D%273.2.13%27">All JIRA issues closed in 3.2.13</a></li>
</ul>
</div>
<div class="section" id="feb-1-2017">
<span id="id10"></span><h3>3.2.12 – Feb 1, 2017<a class="headerlink" href="#feb-1-2017" title="Permalink to this headline">¶</a></h3>
<p>Issues fixed:</p>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-27125">SERVER-27125</a> Arbiters in <code class="docutils literal"><span class="pre">pv1</span></code> should vote no in elections
if they can see a healthy primary of equal or greater priority to the
candidate.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-25012">SERVER-25012</a>: <code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">createIndex</span></code> blocks for duration
of checkpoint while holding locks.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-25865">SERVER-25865</a>: <a class="reference internal" href="../reference/operator/aggregation/group.html#pipe._S_group" title="$group"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$group</span></code></a> operation is slow on
Windows.</li>
<li><a class="reference internal" href="3.2-changelog.html#id68"><span class="std std-ref">3.2.12 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2CTOOLS%2CWT)%20AND%20resolution%3D%27Fixed%27%20and%20fixversion%3D%273.2.12%27">All JIRA issues closed in 3.2.12</a></li>
</ul>
</div>
<div class="section" id="nov-18-2016">
<span id="id11"></span><h3>3.2.11 – Nov 18, 2016<a class="headerlink" href="#nov-18-2016" title="Permalink to this headline">¶</a></h3>
<p>Issues fixed:</p>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-26182">SERVER-26182</a>: In a mixed version replica set with v3.2 and
v3.0 members, a sync of a v3.2 member from a v3.0 member can result
in a query response that exceed 16 MB BSON size limit and crash the
v3.2 member.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-24662">SERVER-24662</a>: Upgrade to Perl compatible regular expressions
(PCRE 8.39).</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-26652">SERVER-26652</a> Invalid definitions in <code class="docutils literal"><span class="pre">systemd</span></code> configuration
for Debian.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-24386">SERVER-24386</a>: <code class="docutils literal"><span class="pre">killCursor</span></code> operation during aggregation
pipeline can cause segmentation fault.</li>
<li><a class="reference internal" href="3.2-changelog.html#id82"><span class="std std-ref">3.2.11 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2CTOOLS%2CWT)%20AND%20resolution%3D%27Fixed%27%20and%20fixversion%3D%273.2.11%27">All JIRA issues closed in 3.2.11</a></li>
</ul>
</div>
<div class="section" id="sep-30-2016">
<span id="id12"></span><h3>3.2.10 – Sep 30, 2016<a class="headerlink" href="#sep-30-2016" title="Permalink to this headline">¶</a></h3>
<p>Issues fixed:</p>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-25974">SERVER-25974</a>: When WT cache utilization is full, application
threads can stall for an extended period of time.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-20306">SERVER-20306</a>: MongoDB with WiredTiger may experience
excessive memory fragmentation, leading to swapping and/or
out-of-memory errors.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-16801">SERVER-16801</a>: When updating a field of one numerical type to
the same number of different numerical type, update operation
considers it as a noop.</li>
<li><a class="reference internal" href="3.2-changelog.html#id92"><span class="std std-ref">3.2.10 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2CTOOLS%2CWT)%20AND%20resolution%3D%27Fixed%27%20and%20fixversion%3D%273.2.10%27">All JIRA issues closed in 3.2.10</a></li>
</ul>
</div>
<div class="section" id="aug-16-2016">
<span id="id13"></span><h3>3.2.9 – Aug 16, 2016<a class="headerlink" href="#aug-16-2016" title="Permalink to this headline">¶</a></h3>
<p>Issues fixed:</p>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-7285">SERVER-7285</a>: Support systemd in future compatible Ubuntu distributions.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/WT-2798">WT-2798</a>: Create operations on WiredTiger when journaling is disabled may
lead to inconsistent data in the event of a crash.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-17856">SERVER-17856</a>: On <a class="reference internal" href="../reference/program/mongod.html#bin.mongod" title="bin.mongod"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongod</span></code></a> instances, users can run
<a class="reference internal" href="../reference/command/currentOp.html#dbcmd.currentOp" title="currentOp"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">currentOp</span></code></a> and <a class="reference internal" href="../reference/command/killOp.html#dbcmd.killOp" title="killOp"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">killOp</span></code></a> on own operations.</li>
<li><a class="reference internal" href="3.2-changelog.html#id104"><span class="std std-ref">3.2.9 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2CTOOLS%2CWT)%20AND%20resolution%3D%27Fixed%27%20and%20fixversion%3D%273.2.9%27">All JIRA issues closed in 3.2.9</a></li>
</ul>
</div>
<div class="section" id="jul-12-2016">
<span id="id14"></span><h3>3.2.8 – Jul 12, 2016<a class="headerlink" href="#jul-12-2016" title="Permalink to this headline">¶</a></h3>
<p>Issues fixed:</p>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-18329">SERVER-18329</a>: Debian 8(Jessie) packages.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-24580">SERVER-24580</a>: Improve performance when WiredTiger cache is
full.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/WT-2696">WT-2696</a>: Race condition on unclean shutdown may miss log
records with large updates.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/WT-2706">WT-2706</a>: Race condition on log file switch can cause missing
log records.</li>
<li><a class="reference internal" href="3.2-changelog.html#id116"><span class="std std-ref">3.2.8 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2CTOOLS%2CWT)%20AND%20resolution%3D%27Fixed%27%20and%20fixversion%3D%273.2.8%27">All JIRA issues closed in 3.2.8</a></li>
</ul>
</div>
<div class="section" id="jun-7-2016">
<span id="id15"></span><h3>3.2.7 – Jun 7, 2016<a class="headerlink" href="#jun-7-2016" title="Permalink to this headline">¶</a></h3>
<p>Issues fixed:</p>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-24054">SERVER-24054</a>: JS segmentation fault on load of certain NaNs.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-24058">SERVER-24058</a>: Connection pool asio doesn’t honor setup timeouts.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-24117">SERVER-24117</a>: Mongo binaries ELF stack has become executable.</li>
<li><a class="reference internal" href="3.2-changelog.html#id131"><span class="std std-ref">3.2.7 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2C%20TOOLS)%20AND%20fixVersion%20%3D%203.2.7%20AND%20resolution%20%3D%20Fixed%20">All JIRA issues closed in 3.2.7</a></li>
</ul>
</div>
<div class="section" id="apr-28-2016">
<span id="id16"></span><h3>3.2.6 – Apr 28, 2016<a class="headerlink" href="#apr-28-2016" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li>First production release of the <a class="reference internal" href="../core/inmemory.html"><span class="doc">in-memory storage engine</span></a>.</li>
</ul>
<p>Issues fixed:</p>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-22970">SERVER-22970</a>: Background index build may result in extra index
key entries that do not correspond to indexed documents.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-22043">SERVER-22043</a>: <a class="reference internal" href="../reference/program/mongo.html#bin.mongo" title="bin.mongo"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongo</span></code></a> shell method <a class="reference internal" href="../reference/method/cursor.count.html#cursor.count" title="cursor.count()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">count()</span></code></a>
ignores read preference.</li>
<li><a class="reference internal" href="3.2-changelog.html#id143"><span class="std std-ref">3.2.6 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2C%20TOOLS)%20AND%20fixVersion%20%3D%203.2.6%20AND%20resolution%20%3D%20Fixed%20">All JIRA issues closed in 3.2.6</a></li>
</ul>
</div>
<div class="section" id="apr-14-2016">
<span id="id17"></span><h3>3.2.5 – Apr 14, 2016<a class="headerlink" href="#apr-14-2016" title="Permalink to this headline">¶</a></h3>
<p>Issues fixed:</p>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-22964">SERVER-22964</a>: IX GlobalLock held while waiting for
WiredTiger cache eviction.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-22831">SERVER-22831</a>: Low query rate with heavy cache pressure
and an idle collection.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21681">SERVER-21681</a>: Include index size stats for in-memory storage
engine.</li>
<li><a class="reference internal" href="3.2-changelog.html#id155"><span class="std std-ref">3.2.5 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2C%20TOOLS)%20AND%20fixVersion%20%3D%203.2.5%20AND%20resolution%20%3D%20Fixed%20">All JIRA issues closed in 3.2.5</a></li>
</ul>
</div>
<div class="section" id="mar-8-2016">
<span id="id18"></span><h3>3.2.4 – Mar 8, 2016<a class="headerlink" href="#mar-8-2016" title="Permalink to this headline">¶</a></h3>
<p>Issues fixed:</p>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-22495">SERVER-22495</a>, <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-22728">SERVER-22728</a>: Update optime when
running with journaling disabled.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-22269">SERVER-22269</a>: Have read concern <code class="docutils literal"><span class="pre">majority</span></code> reflect
journaled state on the primary</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-22683">SERVER-22683</a>:
<a class="reference internal" href="../reference/configuration-options.html#replication.enableMajorityReadConcern" title="replication.enableMajorityReadConcern"><code class="xref mongodb mongodb-setting docutils literal"><span class="pre">replication.enableMajorityReadConcern</span></code></a> ignores actual
setting value and instead implies <code class="docutils literal"><span class="pre">true</span></code>.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-22043">SERVER-22043</a>: <a class="reference internal" href="../reference/method/cursor.count.html#cursor.count" title="cursor.count()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">count()</span></code></a> method in the
<a class="reference internal" href="../reference/program/mongo.html#bin.mongo" title="bin.mongo"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongo</span></code></a> shell does not apply the read preferences.</li>
<li><a class="reference internal" href="3.2-changelog.html#id168"><span class="std std-ref">3.2.4 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2C%20TOOLS)%20AND%20fixVersion%20%3D%203.2.4%20AND%20resolution%20%3D%20Fixed%20">All JIRA issues closed in 3.2.4</a></li>
</ul>
</div>
<div class="section" id="feb-17-2016">
<span id="id19"></span><h3>3.2.3 – Feb 17, 2016<a class="headerlink" href="#feb-17-2016" title="Permalink to this headline">¶</a></h3>
<p>Issues fixed:</p>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-22261">SERVER-22261</a>: For MMAPv1 journaling, the “last sequence
number” file (<code class="docutils literal"><span class="pre">lsn</span></code> file) may be ahead of what is synced to the
data files.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-22167">SERVER-22167</a>: In some cases, insert operations fails to add
the <code class="docutils literal"><span class="pre">_id</span></code> field to large documents.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-22456">SERVER-22456</a>: Increased timeout for querying oplog to 1
minute.</li>
<li><a class="reference internal" href="3.2-changelog.html#id182"><span class="std std-ref">3.2.3 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2C%20TOOLS)%20AND%20fixVersion%20%3D%203.2.3%20AND%20resolution%20%3D%20Fixed%20">All JIRA issues closed in 3.2.3</a></li>
</ul>
</div>
<div class="section" id="feb-16-2016">
<h3>3.2.2 – Feb 16, 2016<a class="headerlink" href="#feb-16-2016" title="Permalink to this headline">¶</a></h3>
<p>Replaced by MongoDB 3.2.3. Users wishing to
run MongoDB 3.2 should skip 3.2.2 and upgrade directly to 3.2.3.</p>
</div>
<div class="section" id="jan-12-2016">
<span id="id20"></span><h3>3.2.1 – Jan 12, 2016<a class="headerlink" href="#jan-12-2016" title="Permalink to this headline">¶</a></h3>
<p>Issues fixed:</p>
<ul class="simple">
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21868">SERVER-21868</a>: During a regular shutdown of a replica set,
secondaries may mark certain replicated but yet to be applied
operations as successfully applied.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-20262">SERVER-20262</a>: Improve insert workload performance with
WiredTiger on Windows.</li>
<li><a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21366">SERVER-21366</a>: Long-running transactions during chunk moves.</li>
<li><a class="reference internal" href="3.2-changelog.html#id197"><span class="std std-ref">3.2.1 Changelog</span></a></li>
<li><a class="reference external" href="https://jira.mongodb.org/issues/?jql=project%20in%20(SERVER%2C%20TOOLS)%20AND%20fixVersion%20%3D%203.2.1%20AND%20resolution%20%3D%20Fixed%20">All JIRA issues closed in 3.2.1</a></li>
</ul>
</div>
</div>
<div class="section" id="wiredtiger-as-default">
<h2>WiredTiger as Default<a class="headerlink" href="#wiredtiger-as-default" title="Permalink to this headline">¶</a></h2>
<p>Starting in 3.2, MongoDB uses the WiredTiger as the default storage
engine.</p>
<p>To specify the MMAPv1 storage engine, you must specify the storage
engine setting either:</p>
<ul>
<li><p class="first">On the command line with the <code class="docutils literal"><span class="pre">--storageEngine</span></code> option:</p>
<div class="button-code-block">
<div class="button-row">
<a class="code-button--copy code-button" role="button">
copy</a>
</div>
<div class="copyable-code-block highlight-sh"><div class="highlight"><pre><span></span>mongod --storageEngine mmapv1
</pre></div>
</div>
</div>
</li>
<li><p class="first">Or in a <a class="reference internal" href="../reference/configuration-options.html"><span class="doc">configuration file</span></a>,
using the <a class="reference internal" href="../reference/configuration-options.html#storage.engine" title="storage.engine"><code class="xref mongodb mongodb-setting docutils literal"><span class="pre">storage.engine</span></code></a> setting:</p>
<div class="button-code-block">
<div class="button-row">
<a class="code-button--copy code-button" role="button">
copy</a>
</div>
<div class="copyable-code-block highlight-yaml"><div class="highlight"><pre><span></span><span class="nt">storage</span><span class="p">:</span>
   <span class="nt">engine</span><span class="p">:</span> <span class="l l-Scalar l-Scalar-Plain">mmapv1</span>
</pre></div>
</div>
</div>
</li>
</ul>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p>For existing deployments, if you do not specify the
<code class="docutils literal"><span class="pre">--storageEngine</span></code> or the <a class="reference internal" href="../reference/configuration-options.html#storage.engine" title="storage.engine"><code class="xref mongodb mongodb-setting docutils literal"><span class="pre">storage.engine</span></code></a> setting,
MongoDB 3.2 can automatically determine the storage engine
used to create the data files in the <code class="docutils literal"><span class="pre">--dbpath</span></code> or
<a class="reference internal" href="../reference/configuration-options.html#storage.dbPath" title="storage.dbPath"><code class="xref mongodb mongodb-setting docutils literal"><span class="pre">storage.dbPath</span></code></a>.</p>
<p class="last">If specifying <code class="docutils literal"><span class="pre">--storageEngine</span></code> or <a class="reference internal" href="../reference/configuration-options.html#storage.engine" title="storage.engine"><code class="xref mongodb mongodb-setting docutils literal"><span class="pre">storage.engine</span></code></a>,
<a class="reference internal" href="../reference/program/mongod.html#bin.mongod" title="bin.mongod"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongod</span></code></a> will not start if <code class="docutils literal"><span class="pre">dbPath</span></code> contains data files
created by a storage engine other than the one specified.</p>
</div>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="3.2-compatibility.html#storage-engine-compatibility"><span class="std std-ref">Default Storage Engine Change</span></a></p>
</div>
<div class="section" id="wiredtiger-default-cache-size">
<h3>WiredTiger Default Cache Size<a class="headerlink" href="#wiredtiger-default-cache-size" title="Permalink to this headline">¶</a></h3>
<p>Starting in MongoDB 3.2, the WiredTiger internal cache, by default,
will use the larger of either:</p>
<ul class="simple">
<li>60% of RAM minus 1 GB, or</li>
<li>1 GB.</li>
</ul>
<p>For more information, see <a class="reference internal" href="../core/wiredtiger.html#wiredtiger-ram"><span class="std std-ref">WiredTiger and Memory Use</span></a>.</p>
</div>
<div class="section" id="wiredtiger-journal-write-frequency">
<h3>WiredTiger Journal Write Frequency<a class="headerlink" href="#wiredtiger-journal-write-frequency" title="Permalink to this headline">¶</a></h3>
<p>MongoDB 3.2 configures WiredTiger to write to the journal files at
every 50 milliseconds. This is in addition to the existing journal write
intervals and conditions. For more information, see <a class="reference internal" href="../core/journaling.html#journal-process"><span class="std std-ref">Journaling Process</span></a>.</p>
</div>
</div>
<div class="section" id="replication-election-enhancements">
<span id="rel-notes-rs-enhancements"></span><h2>Replication Election Enhancements<a class="headerlink" href="#replication-election-enhancements" title="Permalink to this headline">¶</a></h2>
<p>Starting in MongoDB 3.2, MongoDB reduces replica set failover time
and accelerates the detection of multiple simultaneous primaries.</p>
<p>As part of this enhancement, MongoDB introduces a version 1 of the
replication protocol. New replica sets will, by default, use
<a class="reference internal" href="../reference/replica-configuration.html#rsconf.protocolVersion" title="protocolVersion"><code class="xref mongodb mongodb-rsconf docutils literal"><span class="pre">protocolVersion:</span> <span class="pre">1</span></code></a>. Previous versions of
MongoDB use version 0 of the protocol.</p>
<p>In addition, MongoDB introduces a new <a class="reference internal" href="../reference/replica-configuration.html"><span class="doc">replica set configuration</span></a> option
<a class="reference internal" href="../reference/replica-configuration.html#rsconf.settings.electionTimeoutMillis" title="settings.electionTimeoutMillis"><code class="xref mongodb mongodb-rsconf docutils literal"><span class="pre">electionTimeoutMillis</span></code></a>.
<a class="reference internal" href="../reference/replica-configuration.html#rsconf.settings.electionTimeoutMillis" title="settings.electionTimeoutMillis"><code class="xref mongodb mongodb-rsconf docutils literal"><span class="pre">electionTimeoutMillis</span></code></a> specifies the time limit in
milliseconds for detecting when a replica set’s primary is unreachable.</p>
<p><a class="reference internal" href="../reference/replica-configuration.html#rsconf.settings.electionTimeoutMillis" title="settings.electionTimeoutMillis"><code class="xref mongodb mongodb-rsconf docutils literal"><span class="pre">electionTimeoutMillis</span></code></a> only applies if using the
version 1 of the <a class="reference internal" href="../reference/replica-configuration.html#rsconf.protocolVersion" title="protocolVersion"><code class="xref mongodb mongodb-rsconf docutils literal"><span class="pre">replication</span> <span class="pre">protocol</span></code></a>.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="../reference/replica-set-protocol-versions.html"><span class="doc">Replica Set Protocol Version</span></a></p>
</div>
</div>
<div class="section" id="sharded-cluster-enhancements">
<span id="rel-notes-sharded-cluster"></span><h2>Sharded Cluster Enhancements<a class="headerlink" href="#sharded-cluster-enhancements" title="Permalink to this headline">¶</a></h2>
<p>MongoDB 3.2 deprecates the use of three mirrored <a class="reference internal" href="../reference/program/mongod.html#bin.mongod" title="bin.mongod"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongod</span></code></a>
instances for config servers.</p>
<p>Instead, starting in 3.2, the <a class="reference internal" href="../core/sharded-cluster-config-servers.html"><span class="doc">config servers</span></a> for a sharded cluster can be
deployed as a replica set. The replica set config servers must run the
WiredTiger storage engine.</p>
<p>This change improves consistency across the config servers, since
MongoDB can take advantage of the standard replica set read and write
protocols for sharding config data. In addition, this allows a sharded
cluster to have more than 3 config servers since a replica set can have
up to 50 members.</p>
<p>For more information, see <a class="reference internal" href="../core/sharded-cluster-config-servers.html"><span class="doc">Config Servers</span></a>.
To deploy a <strong>new</strong> sharded cluster with replica set config servers,
see <a class="reference internal" href="../tutorial/deploy-shard-cluster.html"><span class="doc">Deploy a Sharded Cluster</span></a>.</p>
<p>MongoDB 3.2 deprecates the use of master-slave replication for
components of sharded clusters.</p>
<p>Starting in 3.2, <a class="reference internal" href="../reference/program/mongos.html#bin.mongos" title="bin.mongos"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongos</span></code></a>, during its startup, will continue
to try to contact the config servers until one becomes available. In
previous versions, <a class="reference internal" href="../reference/program/mongos.html#bin.mongos" title="bin.mongos"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongos</span></code></a>, during its startup, would shut
down if it could not find a config server.</p>
</div>
<div class="section" id="readconcern">
<span id="rel-notes-readconcern"></span><h2><code class="docutils literal"><span class="pre">readConcern</span></code><a class="headerlink" href="#readconcern" title="Permalink to this headline">¶</a></h2>
<p>MongoDB 3.2 introduces the <code class="docutils literal"><span class="pre">readConcern</span></code> query option for replica sets and replica
set shards.  For the <a class="reference internal" href="../core/wiredtiger.html"><span class="doc">WiredTiger storage engine</span></a>, the <code class="docutils literal"><span class="pre">readConcern</span></code> option allows clients to
choose a level of isolation for their reads. You can specify a
<code class="docutils literal"><span class="pre">readConcern</span></code> of <code class="docutils literal"><span class="pre">&quot;majority&quot;</span></code> to read data that has been written to
a majority of nodes and thus cannot be rolled back. By default, MongoDB
uses a <code class="docutils literal"><span class="pre">readConcern</span></code> of <code class="docutils literal"><span class="pre">&quot;local&quot;</span></code> to return the most recent data
available to the node at the time of the query, even if the data has
not been persisted to a majority of nodes and may be rolled back. With
the <a class="reference external" href="https://docs.mongodb.com/v3.2/core/mmapv1">MMAPv1 storage engine</a>, you can only specify a
<code class="docutils literal"><span class="pre">readConcern</span></code> of <code class="docutils literal"><span class="pre">&quot;local&quot;</span></code>.</p>
<p><code class="docutils literal"><span class="pre">readConcern</span></code> requires MongoDB drivers updated for MongoDB 3.2.</p>
<p>For details on <code class="docutils literal"><span class="pre">readConcern</span></code>, including operations that support the
option, see <a class="reference internal" href="../reference/read-concern.html"><span class="doc">Read Concern</span></a>.</p>
</div>
<div class="section" id="partial-indexes">
<h2>Partial Indexes<a class="headerlink" href="#partial-indexes" title="Permalink to this headline">¶</a></h2>
<p>MongoDB 3.2 provides the option to create indexes that only index
the documents in a collection that meet a specified filter expression.
By indexing a subset of the documents in a collection, partial indexes
have lower storage requirements and reduced performance costs for index
creation and maintenance. You can specify a <code class="docutils literal"><span class="pre">partialFilterExpression</span></code>
option for all MongoDB <a class="reference internal" href="../indexes.html#index-types"><span class="std std-ref">index types</span></a>.</p>
<p>The <code class="docutils literal"><span class="pre">partialFilterExpression</span></code> option accepts a document that specifies the
condition using:</p>
<ul class="simple">
<li>equality expressions (i.e. <code class="docutils literal"><span class="pre">field:</span> <span class="pre">value</span></code> or using the <a class="reference internal" href="../reference/operator/query/eq.html#op._S_eq" title="$eq"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$eq</span></code></a>
operator),</li>
<li><a class="reference internal" href="../reference/operator/query/exists.html#op._S_exists" title="$exists"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$exists:</span> <span class="pre">true</span></code></a> expression,</li>
<li><a class="reference internal" href="../reference/operator/query/gt.html#op._S_gt" title="$gt"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$gt</span></code></a>, <a class="reference internal" href="../reference/operator/query/gte.html#op._S_gte" title="$gte"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$gte</span></code></a>, <a class="reference internal" href="../reference/operator/query/lt.html#op._S_lt" title="$lt"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$lt</span></code></a>, <a class="reference internal" href="../reference/operator/query/lte.html#op._S_lte" title="$lte"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$lte</span></code></a> expressions,</li>
<li><a class="reference internal" href="../reference/operator/query/type.html#op._S_type" title="$type"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$type</span></code></a> expressions,</li>
<li><a class="reference internal" href="../reference/operator/query/and.html#op._S_and" title="$and"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$and</span></code></a> operator at the top-level only</li>
</ul>
<p>For details, see <a class="reference internal" href="../core/index-partial.html"><span class="doc">Partial Indexes</span></a>.</p>
</div>
<div class="section" id="document-validation">
<span id="rel-notes-document-validation"></span><h2>Document Validation<a class="headerlink" href="#document-validation" title="Permalink to this headline">¶</a></h2>
<p>Starting in 3.2, MongoDB provides the capability to validate documents
during updates and insertions. Validation rules are specified on a
per-collection basis.</p>
<p>To specify document validation on a new collection, use the new
<code class="docutils literal"><span class="pre">validator</span></code> option in the <a class="reference internal" href="../reference/method/db.createCollection.html#db.createCollection" title="db.createCollection()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.createCollection()</span></code></a> method. To
add document validation to an existing collection, use the new
<code class="docutils literal"><span class="pre">validator</span></code> option in the <a class="reference internal" href="../reference/command/collMod.html#dbcmd.collMod" title="collMod"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">collMod</span></code></a> command. For more
information, see <a class="reference internal" href="../core/schema-validation.html"><span class="doc">Schema Validation</span></a>.</p>
<p>To view the validation specifications for a collection, use the
<a class="reference internal" href="../reference/method/db.getCollectionInfos.html#db.getCollectionInfos" title="db.getCollectionInfos()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.getCollectionInfos()</span></code></a> method.</p>
<p>The following commands can bypass validation per operation using the
new option <code class="docutils literal"><span class="pre">bypassDocumentValidation</span></code>:</p>
<ul class="simple">
<li><a class="reference internal" href="../reference/command/applyOps.html#dbcmd.applyOps" title="applyOps"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">applyOps</span></code></a> command</li>
<li><a class="reference internal" href="../reference/command/findAndModify.html#dbcmd.findAndModify" title="findAndModify"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">findAndModify</span></code></a> command and
<a class="reference internal" href="../reference/method/db.collection.findAndModify.html#db.collection.findAndModify" title="db.collection.findAndModify()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.findAndModify()</span></code></a> method</li>
<li><a class="reference internal" href="../reference/command/mapReduce.html#dbcmd.mapReduce" title="mapReduce"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">mapReduce</span></code></a> command and
<a class="reference internal" href="../reference/method/db.collection.mapReduce.html#db.collection.mapReduce" title="db.collection.mapReduce()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.mapReduce()</span></code></a> method</li>
<li><a class="reference internal" href="../reference/command/insert.html#dbcmd.insert" title="insert"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">insert</span></code></a> command</li>
<li><a class="reference internal" href="../reference/command/update.html#dbcmd.update" title="update"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">update</span></code></a> command</li>
<li><a class="reference internal" href="../reference/operator/aggregation/out.html#pipe._S_out" title="$out"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$out</span></code></a> for the <a class="reference internal" href="../reference/command/aggregate.html#dbcmd.aggregate" title="aggregate"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">aggregate</span></code></a> command and
<a class="reference internal" href="../reference/method/db.collection.aggregate.html#db.collection.aggregate" title="db.collection.aggregate()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.aggregate()</span></code></a> method</li>
</ul>
<p>For deployments that have enabled access control, you must have
<a class="reference internal" href="../reference/privilege-actions.html#bypassDocumentValidation" title="bypassDocumentValidation"><code class="xref mongodb mongodb-authaction docutils literal"><span class="pre">bypassDocumentValidation</span></code></a> action. The built-in roles
<a class="reference internal" href="../reference/built-in-roles.html#dbAdmin" title="dbAdmin"><code class="xref mongodb mongodb-authrole docutils literal"><span class="pre">dbAdmin</span></code></a> and <a class="reference internal" href="../reference/built-in-roles.html#restore" title="restore"><code class="xref mongodb mongodb-authrole docutils literal"><span class="pre">restore</span></code></a> provide this action.</p>
</div>
<div class="section" id="aggregation-framework-enhancements">
<h2>Aggregation Framework Enhancements<a class="headerlink" href="#aggregation-framework-enhancements" title="Permalink to this headline">¶</a></h2>
<p>MongoDB introduces:</p>
<ul class="simple">
<li>New stages, accumulators, and expressions.</li>
<li><a class="reference internal" href="#agg-accumulator-availability"><span class="std std-ref">Availability of accumulator expressions</span></a> in <a class="reference internal" href="../reference/operator/aggregation/project.html#pipe._S_project" title="$project"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$project</span></code></a> stage.</li>
<li><a class="reference internal" href="#agg-shard-optimization"><span class="std std-ref">Performance improvements</span></a> on
sharded clusters.</li>
</ul>
<div class="section" id="new-aggregation-stages">
<h3>New Aggregation Stages<a class="headerlink" href="#new-aggregation-stages" title="Permalink to this headline">¶</a></h3>
<table border="1" class="colwidths-given docutils">
<colgroup>
<col width="10%" />
<col width="40%" />
<col width="50%" />
</colgroup>
<thead valign="bottom">
<tr class="row-odd"><th class="head">Stage</th>
<th class="head">Description</th>
<th class="head">Syntax</th>
</tr>
</thead>
<tbody valign="top">
<tr class="row-even"><td><a class="reference internal" href="../reference/operator/aggregation/sample.html#pipe._S_sample" title="$sample"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$sample</span></code></a></td>
<td>Randomly selects N documents from its input.</td>
<td><code class="docutils literal"><span class="pre">{</span> <span class="pre">$sample:</span> <span class="pre">{</span> <span class="pre">size:</span> <span class="pre">&lt;positive</span> <span class="pre">integer&gt;</span> <span class="pre">}</span> <span class="pre">}</span></code></td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="../reference/operator/aggregation/indexStats.html#pipe._S_indexStats" title="$indexStats"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$indexStats</span></code></a></td>
<td>Returns statistics on index usage.</td>
<td><code class="docutils literal"><span class="pre">{</span> <span class="pre">$indexStats:</span> <span class="pre">{</span> <span class="pre">}</span> <span class="pre">}</span></code></td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="../reference/operator/aggregation/lookup.html#pipe._S_lookup" title="$lookup"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$lookup</span></code></a></td>
<td>Performs a left outer join with another collection.</td>
<td><div class="first last button-code-block">
<div class="button-row">
<a class="code-button--copy code-button" role="button">
copy</a>
</div>
<div class="copyable-code-block highlight-none"><div class="highlight"><pre><span></span>{
   $lookup:
     {
       from: &lt;collection to join&gt;,
       localField: &lt;fieldA&gt;,
       foreignField: &lt;fieldB&gt;,
       as: &lt;output array field&gt;
     }
}
</pre></div>
</div>
</div>
</td>
</tr>
</tbody>
</table>
</div>
<div class="section" id="new-accumulators-for-group-stage">
<h3>New Accumulators for <code class="docutils literal"><span class="pre">$group</span></code> Stage<a class="headerlink" href="#new-accumulators-for-group-stage" title="Permalink to this headline">¶</a></h3>
<table border="1" class="colwidths-given docutils">
<colgroup>
<col width="10%" />
<col width="40%" />
<col width="50%" />
</colgroup>
<thead valign="bottom">
<tr class="row-odd"><th class="head">Accumulator</th>
<th class="head">Description</th>
<th class="head">Syntax</th>
</tr>
</thead>
<tbody valign="top">
<tr class="row-even"><td><a class="reference internal" href="../reference/operator/aggregation/stdDevSamp.html#grp._S_stdDevSamp" title="$stdDevSamp"><code class="xref mongodb mongodb-group docutils literal"><span class="pre">$stdDevSamp</span></code></a></td>
<td>Calculates standard deviation.</td>
<td><code class="docutils literal"><span class="pre">{</span> <span class="pre">$stdDevSamp:</span> <span class="pre">&lt;array&gt;</span> <span class="pre">}</span></code></td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="../reference/operator/aggregation/stdDevPop.html#grp._S_stdDevPop" title="$stdDevPop"><code class="xref mongodb mongodb-group docutils literal"><span class="pre">$stdDevPop</span></code></a></td>
<td>Calculates population standard deviation.</td>
<td><code class="docutils literal"><span class="pre">{</span> <span class="pre">$stdDevPop:</span> <span class="pre">&lt;array&gt;</span> <span class="pre">}</span></code></td>
</tr>
</tbody>
</table>
</div>
<div class="section" id="new-aggregation-arithmetic-operators">
<h3>New Aggregation Arithmetic Operators<a class="headerlink" href="#new-aggregation-arithmetic-operators" title="Permalink to this headline">¶</a></h3>
<table border="1" class="colwidths-given docutils">
<colgroup>
<col width="10%" />
<col width="40%" />
<col width="50%" />
</colgroup>
<thead valign="bottom">
<tr class="row-odd"><th class="head">Operator</th>
<th class="head">Description</th>
<th class="head">Syntax</th>
</tr>
</thead>
<tbody valign="top">
<tr class="row-even"><td><a class="reference internal" href="../reference/operator/aggregation/sqrt.html#exp._S_sqrt" title="$sqrt"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$sqrt</span></code></a></td>
<td>Calculates the square root.</td>
<td><code class="docutils literal"><span class="pre">{</span> <span class="pre">$sqrt:</span> <span class="pre">&lt;number&gt;</span> <span class="pre">}</span></code></td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="../reference/operator/aggregation/abs.html#exp._S_abs" title="$abs"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$abs</span></code></a></td>
<td>Returns the absolute value of a number.</td>
<td><code class="docutils literal"><span class="pre">{</span> <span class="pre">$abs:</span> <span class="pre">&lt;number&gt;</span> <span class="pre">}</span></code></td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="../reference/operator/aggregation/log.html#exp._S_log" title="$log"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$log</span></code></a></td>
<td>Calculates the log of a number in the specified base.</td>
<td><code class="docutils literal"><span class="pre">{</span> <span class="pre">$log:</span> <span class="pre">[</span> <span class="pre">&lt;number&gt;,</span> <span class="pre">&lt;base&gt;</span> <span class="pre">]</span> <span class="pre">}</span></code></td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="../reference/operator/aggregation/log10.html#exp._S_log10" title="$log10"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$log10</span></code></a></td>
<td>Calculates the log base 10 of a number.</td>
<td><code class="docutils literal"><span class="pre">{</span> <span class="pre">$log10:</span> <span class="pre">&lt;number&gt;</span> <span class="pre">}</span></code></td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="../reference/operator/aggregation/ln.html#exp._S_ln" title="$ln"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$ln</span></code></a></td>
<td>Calculates the natural log of a number.</td>
<td><code class="docutils literal"><span class="pre">{</span> <span class="pre">$ln:</span> <span class="pre">&lt;number&gt;</span> <span class="pre">}</span></code></td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="../reference/operator/aggregation/pow.html#exp._S_pow" title="$pow"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$pow</span></code></a></td>
<td>Raises a number to the specified exponent.</td>
<td><code class="docutils literal"><span class="pre">{</span> <span class="pre">$pow:</span> <span class="pre">[</span> <span class="pre">&lt;number&gt;,</span> <span class="pre">&lt;exponent&gt;</span> <span class="pre">]</span> <span class="pre">}</span></code></td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="../reference/operator/aggregation/exp.html#exp._S_exp" title="$exp"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$exp</span></code></a></td>
<td>Raises <em>e</em> to the specified exponent.</td>
<td><code class="docutils literal"><span class="pre">{</span> <span class="pre">exp:</span> <span class="pre">&lt;number&gt;</span> <span class="pre">}</span></code></td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="../reference/operator/aggregation/trunc.html#exp._S_trunc" title="$trunc"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$trunc</span></code></a></td>
<td>Truncates a number to its integer.</td>
<td><code class="docutils literal"><span class="pre">{</span> <span class="pre">$trunc:</span> <span class="pre">&lt;number&gt;</span> <span class="pre">}</span></code></td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="../reference/operator/aggregation/ceil.html#exp._S_ceil" title="$ceil"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$ceil</span></code></a></td>
<td>Returns the smallest integer greater than or equal to the
specified number.</td>
<td><code class="docutils literal"><span class="pre">{</span> <span class="pre">$ceil:</span> <span class="pre">&lt;number&gt;</span> <span class="pre">}</span></code></td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="../reference/operator/aggregation/floor.html#exp._S_floor" title="$floor"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$floor</span></code></a></td>
<td>Returns the largest integer less than or equal to the specified
number.</td>
<td><code class="docutils literal"><span class="pre">{</span> <span class="pre">floor:</span> <span class="pre">&lt;number&gt;</span> <span class="pre">}</span></code></td>
</tr>
</tbody>
</table>
</div>
<div class="section" id="new-aggregation-array-operators">
<h3>New Aggregation Array Operators<a class="headerlink" href="#new-aggregation-array-operators" title="Permalink to this headline">¶</a></h3>
<table border="1" class="colwidths-given docutils">
<colgroup>
<col width="10%" />
<col width="35%" />
<col width="55%" />
</colgroup>
<thead valign="bottom">
<tr class="row-odd"><th class="head">Operator</th>
<th class="head">Description</th>
<th class="head">Syntax</th>
</tr>
</thead>
<tbody valign="top">
<tr class="row-even"><td><a class="reference internal" href="../reference/operator/aggregation/slice.html#exp._S_slice" title="$slice"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$slice</span></code></a></td>
<td>Returns a subset of an array.</td>
<td><p class="first"><code class="docutils literal"><span class="pre">{</span> <span class="pre">$slice:</span> <span class="pre">[</span> <span class="pre">&lt;array&gt;,</span> <span class="pre">&lt;n&gt;</span> <span class="pre">]</span> <span class="pre">}</span></code></p>
<p>or</p>
<p class="last"><code class="docutils literal"><span class="pre">{</span> <span class="pre">$slice:</span> <span class="pre">[</span> <span class="pre">&lt;array&gt;,</span> <span class="pre">&lt;position&gt;,</span> <span class="pre">&lt;n&gt;</span> <span class="pre">]</span> <span class="pre">}</span></code></p>
</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="../reference/operator/aggregation/arrayElemAt.html#exp._S_arrayElemAt" title="$arrayElemAt"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$arrayElemAt</span></code></a></td>
<td>Returns the element at the specified array index.</td>
<td><code class="docutils literal"><span class="pre">{</span> <span class="pre">$arrayElemAt:</span> <span class="pre">[</span> <span class="pre">&lt;array&gt;,</span> <span class="pre">&lt;idx&gt;</span> <span class="pre">]</span> <span class="pre">}</span></code></td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="../reference/operator/aggregation/concatArrays.html#exp._S_concatArrays" title="$concatArrays"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$concatArrays</span></code></a></td>
<td>Concatenates arrays.</td>
<td><div class="first last button-code-block">
<div class="button-row">
<a class="code-button--copy code-button" role="button">
copy</a>
</div>
<div class="copyable-code-block highlight-javascript"><div class="highlight"><pre><span></span><span class="p">{</span>
  <span class="nx">$concatArrays</span><span class="o">:</span> <span class="p">[</span> <span class="o">&lt;</span><span class="nx">array1</span><span class="o">&gt;</span><span class="p">,</span> <span class="o">&lt;</span><span class="nx">array2</span><span class="o">&gt;</span><span class="p">,</span> <span class="p">...</span> <span class="p">]</span>
<span class="p">}</span>
</pre></div>
</div>
</div>
</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="../reference/operator/aggregation/isArray.html#exp._S_isArray" title="$isArray"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$isArray</span></code></a></td>
<td>Determines if the operand is an array.</td>
<td><code class="docutils literal"><span class="pre">{</span> <span class="pre">$isArray:</span> <span class="pre">[</span> <span class="pre">&lt;expression&gt;</span> <span class="pre">]</span> <span class="pre">}</span></code></td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="../reference/operator/aggregation/filter.html#exp._S_filter" title="$filter"><code class="xref mongodb mongodb-expression docutils literal"><span class="pre">$filter</span></code></a></td>
<td>Selects a subset of the array based on the condition.</td>
<td><div class="first last button-code-block">
<div class="button-row">
<a class="code-button--copy code-button" role="button">
copy</a>
</div>
<div class="copyable-code-block highlight-javascript"><div class="highlight"><pre><span></span><span class="p">{</span>
  <span class="nx">$filter</span><span class="o">:</span>
    <span class="p">{</span>
      <span class="nx">input</span><span class="o">:</span> <span class="o">&lt;</span><span class="nx">array</span><span class="o">&gt;</span><span class="p">,</span>
      <span class="nx">as</span><span class="o">:</span> <span class="o">&lt;</span><span class="nx">string</span><span class="o">&gt;</span><span class="p">,</span>
      <span class="nx">cond</span><span class="o">:</span> <span class="o">&lt;</span><span class="nx">expression</span><span class="o">&gt;</span>
    <span class="p">}</span>
<span class="p">}</span>
</pre></div>
</div>
</div>
</td>
</tr>
</tbody>
</table>
</div>
<div class="section" id="accumulator-expression-availability">
<span id="agg-accumulator-availability"></span><h3>Accumulator Expression Availability<a class="headerlink" href="#accumulator-expression-availability" title="Permalink to this headline">¶</a></h3>
<p>Starting in version 3.2, the following accumulator expressions,
previously only available in the <a class="reference internal" href="../reference/operator/aggregation/group.html#pipe._S_group" title="$group"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$group</span></code></a> stage, are now also
available in the <a class="reference internal" href="../reference/operator/aggregation/project.html#pipe._S_project" title="$project"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$project</span></code></a> stage:</p>
<ul class="simple">
<li><a class="reference internal" href="../reference/operator/aggregation/avg.html#grp._S_avg" title="$avg"><code class="xref mongodb mongodb-group docutils literal"><span class="pre">$avg</span></code></a></li>
<li><a class="reference internal" href="../reference/operator/aggregation/min.html#grp._S_min" title="$min"><code class="xref mongodb mongodb-group docutils literal"><span class="pre">$min</span></code></a></li>
<li><a class="reference internal" href="../reference/operator/aggregation/max.html#grp._S_max" title="$max"><code class="xref mongodb mongodb-group docutils literal"><span class="pre">$max</span></code></a></li>
<li><a class="reference internal" href="../reference/operator/aggregation/sum.html#grp._S_sum" title="$sum"><code class="xref mongodb mongodb-group docutils literal"><span class="pre">$sum</span></code></a></li>
<li><a class="reference internal" href="../reference/operator/aggregation/stdDevPop.html#grp._S_stdDevPop" title="$stdDevPop"><code class="xref mongodb mongodb-group docutils literal"><span class="pre">$stdDevPop</span></code></a></li>
<li><a class="reference internal" href="../reference/operator/aggregation/stdDevSamp.html#grp._S_stdDevSamp" title="$stdDevSamp"><code class="xref mongodb mongodb-group docutils literal"><span class="pre">$stdDevSamp</span></code></a></li>
</ul>
<p>When used as part of the <a class="reference internal" href="../reference/operator/aggregation/project.html#pipe._S_project" title="$project"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$project</span></code></a> stage, these accumulator
expressions can accept either:</p>
<ul class="simple">
<li>A single argument: <code class="docutils literal"><span class="pre">&lt;accumulator&gt;</span> <span class="pre">:</span> <span class="pre">&lt;arg&gt;</span></code></li>
<li>Multiple arguments: <code class="docutils literal"><span class="pre">&lt;accumulator&gt;</span> <span class="pre">:</span> <span class="pre">[</span> <span class="pre">&lt;arg1&gt;,</span> <span class="pre">&lt;arg2&gt;,</span> <span class="pre">...</span> <span class="pre">]</span></code></li>
</ul>
</div>
<div class="section" id="general-enhancements">
<h3>General Enhancements<a class="headerlink" href="#general-enhancements" title="Permalink to this headline">¶</a></h3>
<ul>
<li><p class="first">In MongoDB 3.2, <a class="reference internal" href="../reference/operator/aggregation/project.html#pipe._S_project" title="$project"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$project</span></code></a> stage supports using the square
brackets <code class="docutils literal"><span class="pre">[]</span></code> to directly create new array fields. For an example,
see <a class="reference internal" href="../reference/operator/aggregation/project.html#example-project-new-array-fields"><span class="std std-ref">Project New Array Fields</span></a>.</p>
</li>
<li><p class="first">MongoDB 3.2 introduces the <code class="docutils literal"><span class="pre">minDistance</span></code> option for the
<a class="reference internal" href="../reference/operator/aggregation/geoNear.html#pipe._S_geoNear" title="$geoNear"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$geoNear</span></code></a> stage.</p>
</li>
<li><p class="first"><a class="reference internal" href="../reference/operator/aggregation/unwind.html#pipe._S_unwind" title="$unwind"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$unwind</span></code></a> stage no longer errors on non-array operand. If
the operand does not resolve to an array but is not missing, null, or
an empty array, <a class="reference internal" href="../reference/operator/aggregation/unwind.html#pipe._S_unwind" title="$unwind"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$unwind</span></code></a> treats the operand as a single
element array.</p>
<p><a class="reference internal" href="../reference/operator/aggregation/unwind.html#pipe._S_unwind" title="$unwind"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$unwind</span></code></a> stage can:</p>
<ul class="simple">
<li>include the array index of the array element in the output by
specifying a new option <code class="docutils literal"><span class="pre">includeArrayIndex</span></code> in the stage
specification.</li>
<li>output those documents where the array field is missing, null or an
empty array by specifying a new option
<code class="docutils literal"><span class="pre">preserveNullAndEmptyArrays</span></code> in the stage specification.</li>
</ul>
<p>To support these new features, <a class="reference internal" href="../reference/operator/aggregation/unwind.html#pipe._S_unwind" title="$unwind"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$unwind</span></code></a> can now take an
alternate syntax. See <a class="reference internal" href="../reference/operator/aggregation/unwind.html#pipe._S_unwind" title="$unwind"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$unwind</span></code></a> for details.</p>
</li>
</ul>
</div>
<div class="section" id="optimization">
<span id="agg-shard-optimization"></span><h3>Optimization<a class="headerlink" href="#optimization" title="Permalink to this headline">¶</a></h3>
<p>Indexes can <a class="reference internal" href="../core/query-optimization.html#read-operations-covered-query"><span class="std std-ref">cover</span></a> aggregation operations.</p>
<p>MongoDB improves the overall performance of the pipeline
in large sharded clusters.</p>
<p>If the pipeline starts with an exact <a class="reference internal" href="../reference/operator/aggregation/match.html#pipe._S_match" title="$match"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$match</span></code></a> on a shard key,
the entire pipeline runs on the matching shard only. Previously, the
pipeline would have been split, and the work of merging it would have
to be done on the primary shard.</p>
<p>For aggregation operations that run on multiple shards, if the
operations do not require running on the database’s primary shard,
these operations can route the results to any shard to merge the
results and avoid overloading the primary shard for that database.
Aggregation operations that require running on the database’s primary
shard are the <a class="reference internal" href="../reference/operator/aggregation/out.html#pipe._S_out" title="$out"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$out</span></code></a> stage and <a class="reference internal" href="../reference/operator/aggregation/lookup.html#pipe._S_lookup" title="$lookup"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$lookup</span></code></a> stage.</p>
</div>
<div class="section" id="compatibility">
<h3>Compatibility<a class="headerlink" href="#compatibility" title="Permalink to this headline">¶</a></h3>
<p>For compatibility changes, see <a class="reference internal" href="3.2-compatibility.html#agg-compatibility"><span class="std std-ref">Aggregation Compatibility Changes</span></a>.</p>
</div>
</div>
<div class="section" id="mongodb-tools-enhancements">
<h2>MongoDB Tools Enhancements<a class="headerlink" href="#mongodb-tools-enhancements" title="Permalink to this headline">¶</a></h2>
<ul class="simple">
<li><a class="reference internal" href="../reference/program/mongodump.html#bin.mongodump" title="bin.mongodump"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongodump</span></code></a> and <a class="reference internal" href="../reference/program/mongorestore.html#bin.mongorestore" title="bin.mongorestore"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongorestore</span></code></a> add support for
archive files and standard output/input streams with a new
<code class="docutils literal"><span class="pre">--archive</span></code> option. This enhancement allows for the streaming of
the dump data over a network device via a pipe. For examples, see<ul>
<li><a class="reference internal" href="../reference/program/mongodump.html#mongodump-example-archive-file"><span class="std std-ref">mongodump to an Archive File</span></a> and <a class="reference internal" href="../reference/program/mongodump.html#mongodump-example-archive-stdout"><span class="std std-ref">mongodump an Archive to
Standard Output</span></a></li>
<li><a class="reference internal" href="../reference/program/mongorestore.html#mongorestore-example-archive-file"><span class="std std-ref">Restore from an Archive File</span></a> and
<a class="reference internal" href="../reference/program/mongorestore.html#mongorestore-example-archive-stdin"><span class="std std-ref">Restore a Database from Standard Input</span></a>.</li>
</ul>
</li>
<li><a class="reference internal" href="../reference/program/mongodump.html#bin.mongodump" title="bin.mongodump"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongodump</span></code></a> and <a class="reference internal" href="../reference/program/mongorestore.html#bin.mongorestore" title="bin.mongorestore"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongorestore</span></code></a> add support for
compressed data dumps with a new <code class="docutils literal"><span class="pre">--gzip</span></code> option. This enhancement
reduces storage space for the dump files. For examples, see:<ul>
<li><a class="reference internal" href="../reference/program/mongodump.html#mongodump-example-gzip"><span class="std std-ref">Compress mongodump Output</span></a></li>
<li><a class="reference internal" href="../reference/program/mongorestore.html#mongorestore-example-gzip"><span class="std std-ref">Restore from Compressed Data</span></a>.</li>
</ul>
</li>
</ul>
</div>
<div class="section" id="encrypted-storage-engine">
<span id="rel-notes-encryption"></span><h2>Encrypted Storage Engine<a class="headerlink" href="#encrypted-storage-engine" title="Permalink to this headline">¶</a></h2>
<div class="admonition-enterprise-feature admonition">
<p class="first admonition-title">Enterprise Feature</p>
<p class="last">Available in MongoDB Enterprise only.</p>
</div>
<div class="admonition important">
<p class="first admonition-title">Important</p>
<p class="last">Available for the WiredTiger Storage Engine only.</p>
</div>
<p>Encryption at rest, when used in conjunction with transport encryption
and good security policies that protect relevant accounts, passwords,
and encryption keys, can help ensure compliance with security and
privacy standards, including HIPAA, PCI-DSS, and FERPA.</p>
<p>MongoDB Enterprise 3.2 introduces a native encryption option for the
WiredTiger storage engine. This feature allows MongoDB to encrypt data
files such that only parties with the decryption key can decode and
read the data. For detail, see <a class="reference internal" href="../core/security-encryption-at-rest.html#encrypted-storage-engine"><span class="std std-ref">Encrypted Storage Engine</span></a>.</p>
</div>
<div class="section" id="text-search-enhancements">
<h2>Text Search Enhancements<a class="headerlink" href="#text-search-enhancements" title="Permalink to this headline">¶</a></h2>
<div class="section" id="text-index-version-3">
<span id="relnotes-text-index-v3"></span><h3><code class="docutils literal"><span class="pre">text</span></code> Index Version 3<a class="headerlink" href="#text-index-version-3" title="Permalink to this headline">¶</a></h3>
<p>MongoDB 3.2 introduces a version 3 of the <a class="reference internal" href="../core/index-text.html"><span class="doc">text index</span></a>. Key features of the new version of the index are:</p>
<ul class="simple">
<li>Improved <a class="reference internal" href="../core/index-text.html#text-index-case-insensitivity"><span class="std std-ref">case insensitivity</span></a>.</li>
<li><a class="reference internal" href="../core/index-text.html#text-index-diacritic-insensitivity"><span class="std std-ref">Diacritic insensitivity</span></a>.</li>
<li>Additional <a class="reference internal" href="../core/index-text.html#text-index-tokenization-delimiters"><span class="std std-ref">delimiters for tokenization</span></a>.</li>
</ul>
<p>Starting in MongoDB 3.2, version 3 is the default version for new
<a class="reference internal" href="../core/index-text.html"><span class="doc">text</span></a> indexes.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="3.2-compatibility.html#text-index-compatibility"><span class="std std-ref">Text Index Version 3 Compatibility</span></a></p>
</div>
</div>
<div class="section" id="text-operator-enhancements">
<span id="relnotes-text-operator"></span><h3><code class="docutils literal"><span class="pre">$text</span></code> Operator Enhancements<a class="headerlink" href="#text-operator-enhancements" title="Permalink to this headline">¶</a></h3>
<p>The <a class="reference internal" href="../reference/operator/query/text.html#op._S_text" title="$text"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$text</span></code></a> operator adds support for:</p>
<ul class="simple">
<li><a class="reference internal" href="../reference/operator/query/text.html#text-operator-case-sensitivity"><span class="std std-ref">case sensitive text search</span></a>
with the new <code class="docutils literal"><span class="pre">$caseSensitive</span></code> option, and</li>
<li><a class="reference internal" href="../reference/operator/query/text.html#text-operator-diacritic-sensitivity"><span class="std std-ref">diacritic sensitive text search</span></a> with the new
<code class="docutils literal"><span class="pre">$diacriticSensitive</span></code> option.</li>
</ul>
<p>For more information and examples, see the <a class="reference internal" href="../reference/operator/query/text.html#op._S_text" title="$text"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$text</span></code></a> operator
reference sections <a class="reference internal" href="../reference/operator/query/text.html#text-operator-case-sensitivity"><span class="std std-ref">Case Insensitivity</span></a> and
<a class="reference internal" href="../reference/operator/query/text.html#text-operator-diacritic-sensitivity"><span class="std std-ref">Diacritic Insensitivity</span></a>.</p>
</div>
<div class="section" id="support-for-additional-languages">
<h3>Support for Additional Languages<a class="headerlink" href="#support-for-additional-languages" title="Permalink to this headline">¶</a></h3>
<div class="admonition-enterprise-feature admonition">
<p class="first admonition-title">Enterprise Feature</p>
<p class="last">Available in MongoDB Enterprise only.</p>
</div>
<p>Starting in 3.2, MongoDB Enterprise provides support for the
following languages: Arabic, Farsi (specifically Dari and Iranian
Persian dialects), Urdu, Simplified Chinese, and Traditional Chinese.</p>
<p>For details, see <a class="reference internal" href="../tutorial/text-search-with-rlp.html"><span class="doc">Text Search with Basis Technology Rosette Linguistics Platform</span></a>.</p>
</div>
</div>
<div class="section" id="new-storage-engines">
<h2>New Storage Engines<a class="headerlink" href="#new-storage-engines" title="Permalink to this headline">¶</a></h2>
<div class="section" id="inmemory-storage-engine">
<h3><code class="docutils literal"><span class="pre">inMemory</span></code> Storage Engine<a class="headerlink" href="#inmemory-storage-engine" title="Permalink to this headline">¶</a></h3>
<div class="admonition-enterprise-feature admonition">
<p class="first admonition-title">Enterprise Feature</p>
<p class="last">Available in MongoDB Enterprise only.</p>
</div>
<p>MongoDB Enterprise 3.2 provides an in-memory storage engine. Other than some
metadata, the in-memory storage engine does not maintain any on-disk data. By
avoiding disk I/O, the in-memory storage engine allows for more predictable
latency of database operations.</p>
<p>To select this storage engine, specify</p>
<ul class="simple">
<li><code class="docutils literal"><span class="pre">inMemory</span></code> for the <a class="reference internal" href="../reference/program/mongod.html#cmdoption-mongod-storageengine"><code class="xref std std-option docutils literal"><span class="pre">--storageEngine</span></code></a> option or the
<a class="reference internal" href="../reference/configuration-options.html#storage.engine" title="storage.engine"><code class="xref mongodb mongodb-setting docutils literal"><span class="pre">storage.engine</span></code></a> setting.</li>
<li><code class="docutils literal"><span class="pre">--dbpath</span></code>. Although the in-memory storage engine does not write
data to the filesystem, it maintains in the <code class="docutils literal"><span class="pre">--dbpath</span></code> small
metadata files and diagnostic data as well temporary files for building
large indexes.</li>
</ul>
<p>The <code class="docutils literal"><span class="pre">inMemory</span></code> storage engine uses document-level locking. For more details,
see <a class="reference internal" href="../core/inmemory.html"><span class="doc">In-Memory Storage Engine</span></a>.</p>
</div>
<div class="section" id="ephemeralfortest-storage-engine">
<h3><code class="docutils literal"><span class="pre">ephemeralForTest</span></code> Storage Engine<a class="headerlink" href="#ephemeralfortest-storage-engine" title="Permalink to this headline">¶</a></h3>
<p>MongoDB 3.2 provides a new for-test storage engine. Other than some metadata,
the for-test storage engine does not maintain any on-disk data, removing the
need to clean up between test runs. The for-test storage engine is unsupported.</p>
<div class="admonition warning">
<p class="first admonition-title">Warning</p>
<p class="last">For test purposes only. Do not use in production.</p>
</div>
<p>To select this storage engine, specify</p>
<ul class="simple">
<li><code class="docutils literal"><span class="pre">ephemeralForTest</span></code> for the <a class="reference internal" href="../reference/program/mongod.html#cmdoption-mongod-storageengine"><code class="xref std std-option docutils literal"><span class="pre">--storageEngine</span></code></a> option or the
<a class="reference internal" href="../reference/configuration-options.html#storage.engine" title="storage.engine"><code class="xref mongodb mongodb-setting docutils literal"><span class="pre">storage.engine</span></code></a> setting.</li>
<li><code class="docutils literal"><span class="pre">--dbpath</span></code>. Although the for-test storage engine does not write data to
the filesystem, it maintains small metadata files in the <code class="docutils literal"><span class="pre">--dbpath</span></code>.</li>
</ul>
<p>The <code class="docutils literal"><span class="pre">ephemeralForTest</span></code> storage engine uses collection-level locking.</p>
</div>
</div>
<div class="section" id="id21">
<span id="id22"></span><h2>General Enhancements<a class="headerlink" href="#id21" title="Permalink to this headline">¶</a></h2>
<div class="section" id="bit-test-query-operators">
<h3>Bit Test Query Operators<a class="headerlink" href="#bit-test-query-operators" title="Permalink to this headline">¶</a></h3>
<p>MongoDB 3.2 provides new query operators to test bit values:</p>
<ul class="simple">
<li><a class="reference internal" href="../reference/operator/query/bitsAllSet.html#op._S_bitsAllSet" title="$bitsAllSet"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$bitsAllSet</span></code></a></li>
<li><a class="reference internal" href="../reference/operator/query/bitsAllClear.html#op._S_bitsAllClear" title="$bitsAllClear"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$bitsAllClear</span></code></a></li>
<li><a class="reference internal" href="../reference/operator/query/bitsAnySet.html#op._S_bitsAnySet" title="$bitsAnySet"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$bitsAnySet</span></code></a></li>
<li><a class="reference internal" href="../reference/operator/query/bitsAnyClear.html#op._S_bitsAnyClear" title="$bitsAnyClear"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$bitsAnyClear</span></code></a></li>
</ul>
</div>
<div class="section" id="spidermonkey-javascript-engine">
<h3>SpiderMonkey JavaScript Engine<a class="headerlink" href="#spidermonkey-javascript-engine" title="Permalink to this headline">¶</a></h3>
<p>MongoDB 3.2 uses SpiderMonkey as the JavaScript engine for the
<a class="reference internal" href="../reference/program/mongo.html#bin.mongo" title="bin.mongo"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongo</span></code></a> shell and <a class="reference internal" href="../reference/program/mongod.html#bin.mongod" title="bin.mongod"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongod</span></code></a> server. SpiderMonkey
provides support for additional platforms and has an improved memory
management model.</p>
<p>This change affects all JavaScript behavior including the commands
<a class="reference internal" href="../reference/command/mapReduce.html#dbcmd.mapReduce" title="mapReduce"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">mapReduce</span></code></a>, <a class="reference external" href="https://docs.mongodb.com/v3.2/reference/command/group">group</a>, and the query operator
<a class="reference internal" href="../reference/operator/query/where.html#op._S_where" title="$where"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$where</span></code></a>; <em>however</em>, this change should be completely
transparent to the user.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="3.2-compatibility.html#spidermonkey-compatibility"><span class="std std-ref">SpiderMonkey Compatibility Changes</span></a></p>
</div>
</div>
<div class="section" id="mongo-shell-and-crud-api">
<h3><code class="docutils literal"><span class="pre">mongo</span></code> Shell and CRUD API<a class="headerlink" href="#mongo-shell-and-crud-api" title="Permalink to this headline">¶</a></h3>
<p>To provide consistency with the MongoDB drivers’ CRUD
(Create/Read/Update/Delete) API, the <a class="reference internal" href="../reference/program/mongo.html#bin.mongo" title="bin.mongo"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongo</span></code></a> shell introduces
additional CRUD methods that are consistent with the drivers’ CRUD API:</p>
<table border="1" class="docutils">
<colgroup>
<col width="50%" />
<col width="50%" />
</colgroup>
<thead valign="bottom">
<tr class="row-odd"><th class="head">New API</th>
<th class="head">Description</th>
</tr>
</thead>
<tbody valign="top">
<tr class="row-even"><td><a class="reference internal" href="../reference/method/db.collection.bulkWrite.html#db.collection.bulkWrite" title="db.collection.bulkWrite()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.bulkWrite()</span></code></a></td>
<td><p class="first">Equivalent to initializing <a class="reference internal" href="../reference/method/Bulk.html#Bulk" title="Bulk()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">Bulk()</span></code></a> operations builder,
using <a class="reference internal" href="../reference/method/Bulk.html#bulk-methods"><span class="std std-ref">Bulk methods</span></a> to add operations, and
running <a class="reference internal" href="../reference/method/Bulk.execute.html#Bulk.execute" title="Bulk.execute()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">Bulk.execute()</span></code></a> to execute the operations.</p>
<p class="last">MongoDB 3.2 deprecates <a class="reference internal" href="../reference/method/Bulk.html#Bulk" title="Bulk()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">Bulk()</span></code></a> and its associated
<a class="reference internal" href="../reference/method/js-bulk.html"><span class="doc">methods</span></a>.</p>
</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="../reference/method/db.collection.deleteMany.html#db.collection.deleteMany" title="db.collection.deleteMany()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.deleteMany()</span></code></a></td>
<td>Equivalent to <a class="reference internal" href="../reference/method/db.collection.remove.html#db.collection.remove" title="db.collection.remove()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.remove()</span></code></a>.</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="../reference/method/db.collection.deleteOne.html#db.collection.deleteOne" title="db.collection.deleteOne()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.deleteOne()</span></code></a></td>
<td><p class="first">Equivalent to <a class="reference internal" href="../reference/method/db.collection.remove.html#db.collection.remove" title="db.collection.remove()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.remove()</span></code></a> with the
<code class="docutils literal"><span class="pre">justOne</span></code> set to true; i.e.</p>
<p class="last"><a class="reference internal" href="../reference/method/db.collection.remove.html#db.collection.remove" title="db.collection.remove"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.remove(</span> <span class="pre">&lt;query&gt;,</span> <span class="pre">true</span> <span class="pre">)</span></code></a> or
<a class="reference internal" href="../reference/method/db.collection.remove.html#db.collection.remove" title="db.collection.remove"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.remove(</span> <span class="pre">&lt;query&gt;,</span> <span class="pre">{</span> <span class="pre">justOne:</span> <span class="pre">true</span> <span class="pre">}</span> <span class="pre">)</span></code></a>.</p>
</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="../reference/method/db.collection.findOneAndDelete.html#db.collection.findOneAndDelete" title="db.collection.findOneAndDelete()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.findOneAndDelete()</span></code></a></td>
<td>Equivalent to <a class="reference internal" href="../reference/method/db.collection.findAndModify.html#db.collection.findAndModify" title="db.collection.findAndModify()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.findAndModify()</span></code></a> method
with <code class="docutils literal"><span class="pre">remove</span></code> set to true.</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="../reference/method/db.collection.findOneAndReplace.html#db.collection.findOneAndReplace" title="db.collection.findOneAndReplace()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.findOneAndReplace()</span></code></a></td>
<td>Equivalent to <a class="reference internal" href="../reference/method/db.collection.findAndModify.html#db.collection.findAndModify" title="db.collection.findAndModify()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.findAndModify()</span></code></a> method
with <code class="docutils literal"><span class="pre">update</span></code> set to a replacement document.</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="../reference/method/db.collection.findOneAndUpdate.html#db.collection.findOneAndUpdate" title="db.collection.findOneAndUpdate()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.findOneAndUpdate()</span></code></a></td>
<td>Equivalent to <a class="reference internal" href="../reference/method/db.collection.findAndModify.html#db.collection.findAndModify" title="db.collection.findAndModify()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.findAndModify()</span></code></a> method
with <code class="docutils literal"><span class="pre">update</span></code> set to a document that specifies modifications
using <a class="reference internal" href="../reference/operator/update.html"><span class="doc">update operators</span></a>.</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="../reference/method/db.collection.insertMany.html#db.collection.insertMany" title="db.collection.insertMany()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.insertMany()</span></code></a></td>
<td>Equivalent to <a class="reference internal" href="../reference/method/db.collection.insert.html#db.collection.insert" title="db.collection.insert()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.insert()</span></code></a> method
with an array of documents as the parameter.</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="../reference/method/db.collection.insertOne.html#db.collection.insertOne" title="db.collection.insertOne()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.insertOne()</span></code></a></td>
<td>Equivalent to <a class="reference internal" href="../reference/method/db.collection.insert.html#db.collection.insert" title="db.collection.insert()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.insert()</span></code></a> method
with a single document as the parameter.</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="../reference/method/db.collection.replaceOne.html#db.collection.replaceOne" title="db.collection.replaceOne()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.replaceOne()</span></code></a></td>
<td>Equivalent to <a class="reference internal" href="../reference/method/db.collection.update.html#db.collection.update" title="db.collection.update()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.update(</span> <span class="pre">&lt;query&gt;,</span>
<span class="pre">&lt;update&gt;</span> <span class="pre">)</span></code></a> method with a replacement
document as the <code class="docutils literal"><span class="pre">&lt;update&gt;</span></code> parameter.</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="../reference/method/db.collection.updateMany.html#db.collection.updateMany" title="db.collection.updateMany()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.updateMany()</span></code></a></td>
<td>Equivalent to <a class="reference internal" href="../reference/method/db.collection.update.html#db.collection.update" title="db.collection.update()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.update(</span> <span class="pre">&lt;query&gt;,</span>
<span class="pre">&lt;update&gt;,</span> <span class="pre">{</span> <span class="pre">multi:</span> <span class="pre">true,</span> <span class="pre">...</span> <span class="pre">})</span></code></a>
method with an <code class="docutils literal"><span class="pre">&lt;update&gt;</span></code> document that specifies
modifications using <a class="reference internal" href="../reference/operator/update.html"><span class="doc">update operators</span></a> and the <code class="docutils literal"><span class="pre">multi</span></code> option set to
true.</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="../reference/method/db.collection.updateOne.html#db.collection.updateOne" title="db.collection.updateOne()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.updateOne()</span></code></a></td>
<td>Equivalent to <a class="reference internal" href="../reference/method/db.collection.update.html#db.collection.update" title="db.collection.update()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.update(</span> <span class="pre">&lt;query&gt;,</span>
<span class="pre">&lt;update&gt;</span> <span class="pre">)</span></code></a> method with an
<code class="docutils literal"><span class="pre">&lt;update&gt;</span></code> document that specifies modifications using
<a class="reference internal" href="../reference/operator/update.html"><span class="doc">update operators</span></a>.</td>
</tr>
</tbody>
</table>
</div>
<div class="section" id="wiredtiger-and-fsynclock">
<h3>WiredTiger and <code class="docutils literal"><span class="pre">fsyncLock</span></code><a class="headerlink" href="#wiredtiger-and-fsynclock" title="Permalink to this headline">¶</a></h3>
<p>Starting in MongoDB 3.2, the WiredTiger storage engine supports the
<a class="reference internal" href="../reference/command/fsync.html#dbcmd.fsync" title="fsync"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">fsync</span></code></a> command with the <code class="docutils literal"><span class="pre">lock</span></code> option or the
<a class="reference internal" href="../reference/program/mongo.html#bin.mongo" title="bin.mongo"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongo</span></code></a> shell method <a class="reference internal" href="../reference/method/db.fsyncLock.html#db.fsyncLock" title="db.fsyncLock()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.fsyncLock()</span></code></a>. That is, for
the WiredTiger storage engine, these operations can guarantee that the
data files do not change, ensuring consistency for the purposes of
creating backups.</p>
</div>
<div class="section" id="platform-support">
<h3>Platform Support<a class="headerlink" href="#platform-support" title="Permalink to this headline">¶</a></h3>
<p>Starting in 3.2, 32-bit binaries are deprecated and will be
unavailable in future releases.</p>
<p>MongoDB 3.2 also deprecates support for Red Hat Enterprise Linux 5.</p>
</div>
<div class="section" id="type-operator-accepts-string-aliases">
<h3><code class="docutils literal"><span class="pre">$type</span></code> Operator Accepts String Aliases<a class="headerlink" href="#type-operator-accepts-string-aliases" title="Permalink to this headline">¶</a></h3>
<p><a class="reference internal" href="../reference/operator/query/type.html#op._S_type" title="$type"><code class="xref mongodb mongodb-query docutils literal"><span class="pre">$type</span></code></a> operator accepts string aliases for the BSON types in
addition to the numbers corresponding to the BSON types.</p>
</div>
<div class="section" id="explain-support-for-distinct-operation">
<h3><code class="docutils literal"><span class="pre">explain()</span></code> Support for <code class="docutils literal"><span class="pre">distinct()</span></code> Operation<a class="headerlink" href="#explain-support-for-distinct-operation" title="Permalink to this headline">¶</a></h3>
<p><a class="reference internal" href="../reference/method/db.collection.explain.html#db.collection.explain" title="db.collection.explain()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.explain()</span></code></a> adds support for
<a class="reference internal" href="../reference/method/db.collection.distinct.html#db.collection.distinct" title="db.collection.distinct()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.distinct()</span></code></a> method. For more information, see
<a class="reference internal" href="../reference/method/db.collection.explain.html#db.collection.explain" title="db.collection.explain()"><code class="xref mongodb mongodb-method docutils literal"><span class="pre">db.collection.explain()</span></code></a>.</p>
</div>
<div class="section" id="explain-support-for-findandmodify-and-distinct-commands">
<h3><code class="docutils literal"><span class="pre">explain</span></code> Support for <code class="docutils literal"><span class="pre">findAndModify</span></code> and <code class="docutils literal"><span class="pre">distinct</span></code> Commands<a class="headerlink" href="#explain-support-for-findandmodify-and-distinct-commands" title="Permalink to this headline">¶</a></h3>
<p><a class="reference internal" href="../reference/command/explain.html#dbcmd.explain" title="explain"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">explain</span></code></a> adds support for the <a class="reference internal" href="../reference/command/distinct.html#dbcmd.distinct" title="distinct"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">distinct</span></code></a> and
<a class="reference internal" href="../reference/command/findAndModify.html#dbcmd.findAndModify" title="findAndModify"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">findAndModify</span></code></a> commands. For more information, see
<a class="reference internal" href="../reference/command/explain.html#dbcmd.explain" title="explain"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">explain</span></code></a>.</p>
</div>
<div class="section" id="deprecation-of-the-http-interface">
<h3>Deprecation of the HTTP Interface<a class="headerlink" href="#deprecation-of-the-http-interface" title="Permalink to this headline">¶</a></h3>
<p>Starting in 3.2, MongoDB deprecates its HTTP interface.</p>
</div>
<div class="section" id="keysexamined-count-includes-the-last-scanned-key">
<h3><code class="docutils literal"><span class="pre">keysExamined</span></code> Count Includes the Last Scanned Key<a class="headerlink" href="#keysexamined-count-includes-the-last-scanned-key" title="Permalink to this headline">¶</a></h3>
<p>For <code class="docutils literal"><span class="pre">explain</span></code> operations run in <code class="docutils literal"><span class="pre">executionStats</span></code> or
<code class="docutils literal"><span class="pre">allPlansExecution</span></code> mode, the <a class="reference internal" href="../reference/explain-results.html"><span class="doc">explain output</span></a> contains the <code class="docutils literal"><span class="pre">keysExamined</span></code> statistic,
representing the number of index keys examined during index scans.</p>
<p>Prior to 3.2, <code class="docutils literal"><span class="pre">keysExamined</span></code> count in some queries did not include
the last scanned key. As of 3.2 this error has been corrected. For more
information, see :data:`
~explain.executionStats.executionStages.inputStage.keysExamined`.</p>
<p>The diagnostic logs and the system profiler report on this statistic.</p>
</div>
<div class="section" id="geospatial-optimization">
<span id="relnotes-2dsphere-index"></span><h3>Geospatial Optimization<a class="headerlink" href="#geospatial-optimization" title="Permalink to this headline">¶</a></h3>
<p>MongoDB 3.2 introduces version 3 of <a class="reference internal" href="../core/2dsphere.html"><span class="doc">2dsphere
indexes</span></a>, which index <a class="reference internal" href="../reference/geojson.html"><span class="doc">GeoJSON geometries</span></a> at a finer gradation. The new version improves
performance of <a class="reference internal" href="../core/2dsphere.html"><span class="doc">2dsphere index</span></a> queries over
smaller regions. In addition, for both <a class="reference internal" href="../core/2d.html"><span class="doc">2d indexes</span></a> and
<a class="reference internal" href="../core/2dsphere.html"><span class="doc">2dsphere indexes</span></a>, the performance of
geoNear queries has been improved for dense datasets.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<p class="last"><a class="reference internal" href="3.2-compatibility.html#dsphere-index-compatibility"><span class="std std-ref">2dsphere Index Version 3 Compatibility</span></a></p>
</div>
</div>
<div class="section" id="diagnostic-data-capture">
<span id="id23"></span><h3>Diagnostic Data Capture<a class="headerlink" href="#diagnostic-data-capture" title="Permalink to this headline">¶</a></h3>
<p>To facilitate analysis of the MongoDB server behavior by MongoDB
engineers, MongoDB 3.2 introduces a diagnostic data collection
mechanism for logging server statistics to diagnostic files at periodic
intervals. By default, the mechanism captures data at 1 second
intervals. To modify the interval, see
<a class="reference internal" href="../reference/parameters.html#param.diagnosticDataCollectionPeriodMillis" title="diagnosticDataCollectionPeriodMillis"><code class="xref mongodb mongodb-parameter docutils literal"><span class="pre">diagnosticDataCollectionPeriodMillis</span></code></a>.</p>
<p>MongoDB creates a <code class="docutils literal"><span class="pre">diagnostic.data</span></code> directory under the
<a class="reference internal" href="../reference/program/mongod.html#bin.mongod" title="bin.mongod"><code class="xref mongodb mongodb-binary docutils literal"><span class="pre">mongod</span></code></a> instance’s <code class="docutils literal"><span class="pre">--dbpath</span></code> or <a class="reference internal" href="../reference/configuration-options.html#storage.dbPath" title="storage.dbPath"><code class="xref mongodb mongodb-setting docutils literal"><span class="pre">storage.dbPath</span></code></a>.
The diagnostic data is stored in files under this directory.</p>
<p>The maximum size of the diagnostic files is configurable with the
<a class="reference internal" href="../reference/parameters.html#param.diagnosticDataCollectionFileSizeMB" title="diagnosticDataCollectionFileSizeMB"><code class="xref mongodb mongodb-parameter docutils literal"><span class="pre">diagnosticDataCollectionFileSizeMB</span></code></a>, and the maximum size
of the <code class="docutils literal"><span class="pre">diagnostic.data</span></code> directory is configurable with
<a class="reference internal" href="../reference/parameters.html#param.diagnosticDataCollectionDirectorySizeMB" title="diagnosticDataCollectionDirectorySizeMB"><code class="xref mongodb mongodb-parameter docutils literal"><span class="pre">diagnosticDataCollectionDirectorySizeMB</span></code></a>.</p>
<p>The default values for the capture interval and the maximum sizes are
chosen to provide useful data to MongoDB engineers with minimal impact
on performance and storage size. Typically, these values will only need
modifications as requested by MongoDB engineers for specific diagnostic
purposes.</p>
</div>
<div class="section" id="write-concern">
<h3>Write Concern<a class="headerlink" href="#write-concern" title="Permalink to this headline">¶</a></h3>
<ul class="simple">
<li>For replica sets using <a class="reference internal" href="../reference/replica-configuration.html#rsconf.protocolVersion" title="protocolVersion"><code class="xref mongodb mongodb-rsconf docutils literal"><span class="pre">protocolVersion:</span> <span class="pre">1</span></code></a>, secondaries acknowledge write operations after the
secondary members have written to their respective on-disk
<a class="reference internal" href="../core/journaling.html"><span class="doc">journals</span></a>, regardless of the <a class="reference internal" href="../reference/write-concern.html#wc-j"><span class="std std-ref">j</span></a>
option.</li>
<li>For replica sets using <a class="reference internal" href="../reference/replica-configuration.html#rsconf.protocolVersion" title="protocolVersion"><code class="xref mongodb mongodb-rsconf docutils literal"><span class="pre">protocolVersion:</span> <span class="pre">1</span></code></a>, <a class="reference internal" href="../reference/write-concern.html#writeconcern.&quot;majority&quot;" title="&quot;majority&quot;"><code class="xref mongodb mongodb-writeconcern docutils literal"><span class="pre">w:</span> <span class="pre">&quot;majority&quot;</span></code></a>
implies <a class="reference internal" href="../reference/write-concern.html#wc-j"><span class="std std-ref">j: true</span></a>.</li>
<li>With <a class="reference internal" href="../reference/write-concern.html#writeconcern.j" title="j"><code class="xref mongodb mongodb-writeconcern docutils literal"><span class="pre">j:</span> <span class="pre">true</span></code></a>, MongoDB returns only after the
requested number of members, including the primary, have written to the
journal. Previously <a class="reference internal" href="../reference/write-concern.html#writeconcern.j" title="j"><code class="xref mongodb mongodb-writeconcern docutils literal"><span class="pre">j:</span> <span class="pre">true</span></code></a> write concern in a
replica set only requires the <a class="reference internal" href="../reference/glossary.html#term-primary"><span class="xref std std-term">primary</span></a> to write to the journal,
regardless of the <a class="reference internal" href="../reference/write-concern.html#wc-w"><span class="std std-ref">w: &lt;value&gt;</span></a> write concern.</li>
</ul>
</div>
<div class="section" id="journalcommitinterval-for-wiredtiger">
<h3><code class="docutils literal"><span class="pre">journalCommitInterval</span></code> for WiredTiger<a class="headerlink" href="#journalcommitinterval-for-wiredtiger" title="Permalink to this headline">¶</a></h3>
<p>MongoDB 3.2 adds support for specifying the journal commit interval for
the WiredTiger storage engine. See <a class="reference internal" href="../reference/program/mongod.html#cmdoption-mongod-journalcommitinterval"><code class="xref std std-option docutils literal"><span class="pre">--journalCommitInterval</span></code></a>
option. In previous versions, the option is applicable to MMAPv1
storage engine only.</p>
<p>For the corresponding configuration file setting, MongoDB 3.2 adds the
<a class="reference external" href="https://docs.mongodb.com/v3.2/reference/configuration-options/#storage.journal.commitIntervalMs">storage.journal.commitIntervalMs</a>
setting and deprecates <a class="reference external" href="https://docs.mongodb.com/v3.2/reference/configuration-options/#storage.mmapv1.journal.commitInterval Ms">storage.mmapv1.journal.commitIntervalMs</a>. The deprecated <a class="reference external" href="https://docs.mongodb.com/v3.2/reference/configuration-options/#storage.mmapv1.journal.commitInterval Ms">storage.mmapv1.journal.commitIntervalMs</a> setting acts as an alias to the new
<a class="reference external" href="https://docs.mongodb.com/v3.2/reference/configuration-options/#storage.journal.commitIntervalMs">storage.journal.commitIntervalMs</a>
setting.</p>
</div>
</div>
<div class="section" id="changes-affecting-compatibility">
<h2>Changes Affecting Compatibility<a class="headerlink" href="#changes-affecting-compatibility" title="Permalink to this headline">¶</a></h2>
<p>Some MongoDB 3.2 changes can affect compatibility and may require user
actions. For a detailed list of compatibility changes, see
<a class="reference internal" href="3.2-compatibility.html"><span class="doc">Compatibility Changes in MongoDB 3.2</span></a>.</p>
<div class="toctree-wrapper hidden compound">
<ul>
<li class="toctree-l1"><a class="reference internal" href="3.2-compatibility.html">Compatibility Changes in MongoDB 3.2</a><ul>
<li class="toctree-l2"><a class="reference internal" href="3.2-compatibility.html#default-storage-engine-change">Default Storage Engine Change</a></li>
<li class="toctree-l2"><a class="reference internal" href="3.2-compatibility.html#index-changes">Index Changes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-compatibility.html#version-0-indexes">Version 0 Indexes</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-compatibility.html#text-index-version-3-compatibility">Text Index Version 3 Compatibility</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-compatibility.html#dsphere-index-version-3-compatibility"><code class="docutils literal"><span class="pre">2dsphere</span></code> Index Version 3 Compatibility</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-compatibility.html#aggregation-compatibility-changes">Aggregation Compatibility Changes</a></li>
<li class="toctree-l2"><a class="reference internal" href="3.2-compatibility.html#spidermonkey-compatibility-changes">SpiderMonkey Compatibility Changes</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-javascript.html">JavaScript Changes in MongoDB 3.2</a><ul>
<li class="toctree-l4"><a class="reference internal" href="3.2-javascript.html#modernized-javascript-implementation-es6">Modernized JavaScript Implementation (ES6)</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-javascript.html#changes-to-the-mongo-shell">Changes to the <code class="docutils literal"><span class="pre">mongo</span></code> Shell</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-javascript.html#removed-non-standard-v8-features">Removed Non-Standard V8 Features</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-compatibility.html#replica-set-configuration-validation">Replica Set Configuration Validation</a></li>
<li class="toctree-l2"><a class="reference internal" href="3.2-compatibility.html#driver-compatibility-changes">Driver Compatibility Changes</a></li>
<li class="toctree-l2"><a class="reference internal" href="3.2-compatibility.html#general-compatibility-changes">General Compatibility Changes</a></li>
<li class="toctree-l2"><a class="reference internal" href="3.2-compatibility.html#additional-information">Additional Information</a></li>
</ul>
</li>
</ul>
</div>
</div>
<div class="section" id="upgrade-process">
<h2>Upgrade Process<a class="headerlink" href="#upgrade-process" title="Permalink to this headline">¶</a></h2>
<div class="toctree-wrapper hidden compound">
<ul>
<li class="toctree-l1"><a class="reference internal" href="3.2-upgrade.html">Upgrade MongoDB to 3.2</a><ul>
<li class="toctree-l2"><a class="reference internal" href="3.2-upgrade.html#upgrade-recommendations-and-checklists">Upgrade Recommendations and Checklists</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-upgrade.html#upgrade-requirements">Upgrade Requirements</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-upgrade.html#preparedness">Preparedness</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-upgrade.html#upgrade-standalone-mongod-instance-to-mongodb-3-2">Upgrade Standalone <code class="docutils literal"><span class="pre">mongod</span></code> Instance to MongoDB 3.2</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-upgrade.html#upgrade-with-package-manager">Upgrade with Package Manager</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-upgrade.html#manual-upgrade">Manual Upgrade</a><ul>
<li class="toctree-l4"><a class="reference internal" href="3.2-upgrade.html#download-3-2-binaries">Download 3.2 binaries.</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-upgrade.html#replace-with-3-2-binaries">Replace with 3.2 binaries</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-upgrade.html#upgrade-a-replica-set-to-3-2">Upgrade a Replica Set to 3.2</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-upgrade.html#prerequisites">Prerequisites</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-upgrade.html#upgrade-binaries">Upgrade Binaries</a><ul>
<li class="toctree-l4"><a class="reference internal" href="3.2-upgrade.html#upgrade-secondary-members-of-the-replica-set">Upgrade secondary members of the replica set.</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-upgrade.html#step-down-the-replica-set-primary">Step down the replica set primary.</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-upgrade.html#upgrade-the-primary">Upgrade the primary.</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-upgrade.html#upgrade-a-sharded-cluster-to-3-2">Upgrade a Sharded Cluster to 3.2</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-upgrade.html#id1">Prerequisites</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-upgrade.html#id2">Upgrade Binaries</a><ul>
<li class="toctree-l4"><a class="reference internal" href="3.2-upgrade.html#disable-the-balancer">Disable the Balancer.</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-upgrade.html#upgrade-the-shards">Upgrade the shards.</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-upgrade.html#upgrade-the-config-servers">Upgrade the config servers.</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-upgrade.html#upgrade-the-mongos-instances">Upgrade the <code class="docutils literal"><span class="pre">mongos</span></code> instances.</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-upgrade.html#re-enable-the-balancer">Re-enable the balancer.</a></li>
</ul>
</li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="3.2-downgrade.html">Downgrade MongoDB from 3.2</a><ul>
<li class="toctree-l2"><a class="reference internal" href="3.2-downgrade.html#downgrade-recommendations-and-checklist">Downgrade Recommendations and Checklist</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-downgrade.html#downgrade-path">Downgrade Path</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-downgrade.html#preparedness">Preparedness</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-downgrade.html#procedures">Procedures</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-downgrade.html#prerequisites">Prerequisites</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-downgrade.html#text-index-version-check">Text Index Version Check</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-downgrade.html#dsphere-index-version-check"><code class="docutils literal"><span class="pre">2dsphere</span></code> Index Version Check</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-downgrade.html#partial-indexes-check">Partial Indexes Check</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-downgrade.html#downgrade-a-standalone-mongod-instance">Downgrade a Standalone <code class="docutils literal"><span class="pre">mongod</span></code> Instance</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-downgrade.html#download-the-latest-3-0-binaries">Download the latest 3.0 binaries.</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-downgrade.html#restart-with-the-latest-3-0-mongod-instance">Restart with the latest 3.0 <code class="docutils literal"><span class="pre">mongod</span></code> instance.</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-downgrade.html#downgrade-a-3-2-replica-set">Downgrade a 3.2 Replica Set</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-downgrade.html#downgrade-the-protocolversion">Downgrade the protocolVersion.</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-downgrade.html#downgrade-secondary-members-of-the-replica-set">Downgrade secondary members of the replica set.</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-downgrade.html#step-down-the-primary">Step down the primary.</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-downgrade.html#replace-and-restart-former-primary-mongod">Replace and restart former primary <code class="docutils literal"><span class="pre">mongod</span></code>.</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="3.2-downgrade.html#downgrade-a-3-2-sharded-cluster">Downgrade a 3.2 Sharded Cluster</a><ul>
<li class="toctree-l3"><a class="reference internal" href="3.2-downgrade.html#requirements">Requirements</a></li>
<li class="toctree-l3"><a class="reference internal" href="3.2-downgrade.html#downgrade-a-sharded-cluster-with-sccc-config-servers">Downgrade a Sharded Cluster with SCCC Config Servers</a><ul>
<li class="toctree-l4"><a class="reference internal" href="3.2-downgrade.html#disable-the-balancer">Disable the Balancer.</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-downgrade.html#downgrade-each-shard-one-at-a-time">Downgrade each shard, one at a time.</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-downgrade.html#downgrade-the-sccc-config-servers">Downgrade the SCCC config servers.</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-downgrade.html#downgrade-the-mongos-instances">Downgrade the <code class="docutils literal"><span class="pre">mongos</span></code> instances.</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-downgrade.html#re-enable-the-balancer">Re-enable the balancer.</a></li>
</ul>
</li>
<li class="toctree-l3"><a class="reference internal" href="3.2-downgrade.html#downgrade-a-sharded-cluster-with-csrs-config-servers">Downgrade a Sharded Cluster with CSRS Config Servers</a><ul>
<li class="toctree-l4"><a class="reference internal" href="3.2-downgrade.html#id1">Disable the Balancer.</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-downgrade.html#check-the-minoptimeupdaters-value">Check the <code class="docutils literal"><span class="pre">minOpTimeUpdaters</span></code> value.</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-downgrade.html#prepare-csrs-config-servers-for-downgrade">Prepare CSRS Config Servers for downgrade.</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-downgrade.html#update-the-protocolversion-for-each-shard">Update the protocolVersion for each shard.</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-downgrade.html#id3">Downgrade the <code class="docutils literal"><span class="pre">mongos</span></code> instances.</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-downgrade.html#downgrade-config-servers">Downgrade Config Servers.</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-downgrade.html#id4">Downgrade each shard, one at a time.</a></li>
<li class="toctree-l4"><a class="reference internal" href="3.2-downgrade.html#id5">Re-enable the balancer.</a></li>
</ul>
</li>
</ul>
</li>
</ul>
</li>
</ul>
</div>
<p>See <a class="reference internal" href="3.2-upgrade.html"><span class="doc">Upgrade MongoDB to 3.2</span></a> for full upgrade instructions.</p>
</div>
<div class="section" id="known-issues-in-3-2-1">
<h2>Known Issues in 3.2.1<a class="headerlink" href="#known-issues-in-3-2-1" title="Permalink to this headline">¶</a></h2>
<p>List of known issues in the 3.2.1 release:</p>
<ul class="simple">
<li>Clients may fail to discover new primaries when clock skew between
nodes is greater than <code class="docutils literal"><span class="pre">electionTimeout</span></code>: <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21744">SERVER-21744</a></li>
<li><code class="docutils literal"><span class="pre">fromMigrate</span></code> flag never set for deletes in oplog: <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21678">SERVER-21678</a></li>
<li>Running <a class="reference internal" href="../reference/command/explain.html#dbcmd.explain" title="explain"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">explain</span></code></a> with a <a class="reference internal" href="../core/read-preference.html#read-preference"><span class="std std-ref">read preference</span></a> in a v3.2 <code class="docutils literal"><span class="pre">mongo</span></code> shell
connected to a v3.0 <code class="docutils literal"><span class="pre">mongos</span></code> or in a v3.0 <code class="docutils literal"><span class="pre">mongo</span></code> shell connected
to a v3.0 <code class="docutils literal"><span class="pre">mongos</span></code> but with v3.2 shards is incompatible:
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21661">SERVER-21661</a></li>
<li>Results of the connPoolStats command are no longer correct: <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21597">SERVER-21597</a></li>
<li>ApplyOps background index creation may deadlock: <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21583">SERVER-21583</a></li>
<li>Performance regression for <code class="docutils literal"><span class="pre">w:majority</span></code> writes with replica set
protocolVersion 1: <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21581">SERVER-21581</a></li>
<li>Performance regression on unicode-aware text processing logic (text
index v3): <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-19936">SERVER-19936</a></li>
<li>Results from the <a class="reference internal" href="../reference/operator/aggregation/indexStats.html#pipe._S_indexStats" title="$indexStats"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$indexStats</span></code></a> operator do not take into account queries
which use the <a class="reference internal" href="../reference/operator/aggregation/match.html#pipe._S_match" title="$match"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$match</span></code></a> or <a class="reference internal" href="../reference/command/mapReduce.html#dbcmd.mapReduce" title="mapReduce"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">mapReduce</span></code></a> functions: <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-22048">SERVER-22048</a></li>
</ul>
</div>
<div class="section" id="known-issues-in-3-2-0">
<h2>Known Issues in 3.2.0<a class="headerlink" href="#known-issues-in-3-2-0" title="Permalink to this headline">¶</a></h2>
<p>List of known issues in the 3.2.0 release:</p>
<ul class="simple">
<li>findAndModify operations not captured by the profiler: <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21772">SERVER-21772</a></li>
<li><a class="reference internal" href="../reference/command/getMore.html#dbcmd.getMore" title="getMore"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">getMore</span></code></a> command does not set <code class="docutils literal"><span class="pre">&quot;nreturned&quot;</span></code> operation
counter: <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21750">SERVER-21750</a></li>
<li>Clients may fail to discover new primaries when clock skew between
nodes is greater than <code class="docutils literal"><span class="pre">electionTimeout</span></code>: <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21744">SERVER-21744</a></li>
<li><code class="docutils literal"><span class="pre">fromMigrate</span></code> flag never set for deletes in oplog: <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21678">SERVER-21678</a></li>
<li>Running <a class="reference internal" href="../reference/command/explain.html#dbcmd.explain" title="explain"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">explain</span></code></a> with a <a class="reference internal" href="../core/read-preference.html#read-preference"><span class="std std-ref">read preference</span></a> in a v3.2 <code class="docutils literal"><span class="pre">mongo</span></code> shell
connected to a v3.0 <code class="docutils literal"><span class="pre">mongos</span></code> or in a v3.0 <code class="docutils literal"><span class="pre">mongo</span></code> shell connected
to a v3.0 <code class="docutils literal"><span class="pre">mongos</span></code> but with v3.2 shards is incompatible:
<a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21661">SERVER-21661</a></li>
<li>Results of the connPoolStats command are no longer correct: <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21597">SERVER-21597</a></li>
<li>ApplyOps background index creation may deadlock: <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21583">SERVER-21583</a></li>
<li>Performance regression for <code class="docutils literal"><span class="pre">w:majority</span></code> writes with replica set
protocolVersion 1: <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21581">SERVER-21581</a></li>
<li>Performance regression on unicode-aware text processing logic (text
index v3): <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-19936">SERVER-19936</a></li>
<li>Severe performance regression in insert workload under Windows with
WiredTiger: <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-21792">SERVER-21792</a></li>
<li>Results from the <a class="reference internal" href="../reference/operator/aggregation/indexStats.html#pipe._S_indexStats" title="$indexStats"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$indexStats</span></code></a> operator do not take into account queries
which use the <a class="reference internal" href="../reference/operator/aggregation/match.html#pipe._S_match" title="$match"><code class="xref mongodb mongodb-pipeline docutils literal"><span class="pre">$match</span></code></a> or <a class="reference internal" href="../reference/command/mapReduce.html#dbcmd.mapReduce" title="mapReduce"><code class="xref mongodb mongodb-dbcommand docutils literal"><span class="pre">mapReduce</span></code></a> functions: <a class="reference external" href="https://jira.mongodb.org/browse/SERVER-22048">SERVER-22048</a></li>
</ul>
</div>
<div class="section" id="download">
<h2>Download<a class="headerlink" href="#download" title="Permalink to this headline">¶</a></h2>
<p>To download MongoDB 3.2, go to the <a class="reference external" href="http://www.mongodb.org/downloads">downloads page</a>.</p>
<div class="admonition seealso">
<p class="first admonition-title">See also</p>
<ul class="last simple">
<li><a class="reference external" href="https://github.com/mongodb/mongo/blob/v3.2/distsrc/THIRD-PARTY-NOTICES">All Third Party License Notices</a>.</li>
<li><a class="reference external" href="http://bit.ly/1XXomL9">All JIRA issues resolved in 3.2</a>.</li>
</ul>
</div>
</div>
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